Course Profile College and Apprenticeship Mathematics (MAP4C), Grade 12, College Preparation, Combined
Unit 5: Modelling
Time: 18 hours
Activity
5.1 | Activity 5.2 | Activity 5.3 | Activity 5.4
| Activity 5.5 | Activity
5.6 | Activity 5.7 | Activity 5.8
Unit Description
Students examine and
work with a variety of mathematical models in various forms: tables, graphs,
and formulas. Students investigate linear, quadratic, and exponential models in
a context that allows them to develop an understanding of how models are used
and created. Connections are made to occupations, such as game warden and
personal trainer, and sectors, such as travel and tourism, construction,
municipal planning, and business.
|
Activity |
*Time |
Learning Expectations |
Assessment Categories |
Tasks |
|
5.1 |
1.25 hours |
MMV.01, MMV.03,
MM1.01, MM1.03, MM3.04 |
Knowledge/
Understanding Communication |
Examine and make
predictions from a variety of models: linear, quadratic and exponential
graphs and tables |
|
5.2 |
2.5 hours |
MMV.01, MMV.03,
MM1.01, MM1.03, MM1.05, MM3.04 |
Application
Communication |
Gather and graph
light intensity data and work with exponential models |
|
5.3 |
1.25 hours |
MMV.01, MMV.02,
ASV.04, MM1.01, MM1.03, MM2.01, AS4.03 |
Thinking/Inquiry/
Problem Solving Communication |
Examine CPI as an
example of exponential growth, create and analyse graphical and formulaic
models, and make predictions |
|
5.4 |
1.25 hours |
MMV.01, MMV.03,
MM1.01, MM1.03, MM1.04, MM3.04 |
Thinking/Inquiry/
Problem Solving Application |
Make predictions,
analyse quadratic graphs, and find roots graphically or by examining table of
values |
|
5.5 |
1.25 hours |
MMV.01, MMV.03,
MM3.04, MM1.03, MM1.04 |
Application
Communication |
Graph data on
stopping distances under various conditions, analyse model, and predict how
model would change if conditions change |
|
5.6 |
2.5 hours |
MMV.01, MMV.02,
MMV.03, MM2.06, MM2.07, MM3.04, MM1.05 |
Knowledge/
Understanding Application |
Create graphs from
a given quadratic equation for various applications, factor, find roots, and
make decisions |
|
5.7 |
2.5 hours |
MMV.03, MM3.01,
MM3.02, MM3.03 |
Thinking/Inquiry/
Problem Solving Application |
Plan a trip to
visit to see various sports teams play in their hometown while meeting budget
constraints |
|
5.8 |
2.5 hours |
MMV.01, MMV.02,
MMV.03, MM1.05, MM2.01, MM2.02, MM2.04, MM3.03, MM3.04 |
Application
Thinking/Inquiry/ Problem Solving Communication |
Choose appropriate
models to create a formula for calculating costs for building a deck |
* An additional 3
hours are available for skill consolidation.
Time: 1.25 hours
Students model three
different situations. Using graphing technology, students interpolate and
extrapolate to answer questions posed for these scenarios.
Strand(s): Analysis of Mathematical Models
Overall
Expectations
MMV.01 - interpret
and analyse given graphical models;
MMV.03 - interpret
and analyse data given in a variety of forms.
Specific
Expectations
MM1.01 - interpret a
given linear, quadratic, or exponential graph to answer questions, using
language and units appropriate to the context from which the graph was drawn;
MM1.03 - make and
justify a decision or prediction and discuss trends based on a given graph;
MM3.04 - enter data
or a formula into a graphing calculator and retrieve other forms of the model
(e.g., enter data and retrieve a scatter graph or a table of values; enter a
formula and retrieve a table of values or the graph of a function).
·
use of graphing
technology to create scatter plots;
·
use of the
regression features of the calculator (knowledge from previous units in this
course. teachers may need to spend more time on this if they approach the
course in a different order);
·
interpolation and
extrapolation.
·
Have a class set
of graphing calculators available for this lesson.
·
Use graphing
calculators to create scatter plots and graphs;
·
Interpolate and
extrapolate from graphs to interpret and analyse models.
Teacher
Facilitation
·
Introduce the
topic of the activity – The Use of Models.
·
Review with
students the use of the List and the Regression features of the calculator. The
teacher may want to create a reference sheet that students can refer to
throughout the unit.
·
Discuss the
importance of r2 in
determining the appropriateness of a model. Students look for models with r2 as close to 1 as possible.
·
The teacher must
turn on the Diagnostic function of the calculator to get r2.
·
Create one list
of data (in the first quadrant only) that produces a cubic graph.
·
Using the
graphing calculators, demonstrate the use of the regression feature in testing
linear, quadratic, exponential, and cubic relationships. Students notice that
the cubic regression is the only one producing an r2 of 1. (Be careful to have the precision on the
calculators in floating mode as rounded values cause students to make incorrect
choices.)
·
Have students
work through the sample worksheet to investigate the three models.
·
The teacher may
use cooperative learning groups. For example, use a jigsaw strategy, in which a
student from each group learns a particular model, then uses it as an example
to teach the other students in their home group.
Sample Worksheet
Mathematical modelling
is important in many professions. A mathematical model provides a way of
analysing what is happening and helps in making predictions. Presenting a
collection of data in chart or co-ordinate form is one way to model a
situation.
Use the data given
in the three scenarios to produce scatter plots, determine the type of model
demonstrated in each example (remember to look for r2 = 1), and then answer the questions based on the
graph you created.
Scenario
1 – Rescue 911
In a rural
community, fire and paramedic crews must service a large region. They often
cover two or three towns several kilometres apart. These crews travel, on
average, 70 km/h to their destination. The Chief of Station 42 wants to
determine the time required to reach the patient’s home (response time) for his
region. The station is located next to the local hospital. The Chief knows the
distances to each community that he services, including Deerborn, the furthest
community, at 55 km away. Using the data, create a scatter plot showing the relationship
between distance to patient and response time.
|
Distance to Patient (km) |
Response Time (minutes) |
|
10 |
8.6 |
|
15 |
12.9 |
|
40 |
34.3 |
|
50 |
42.9 |
|
55 |
47.1 |
The Chief wants to
analyse several situations quickly so he decides to use a graph. Using your
scatter plot, answer the Chief’s questions:
1. Mrs. Klein lives 52 km from Station 42;
determine the approximate response time.
2. If the crew took 15 minutes to arrive at a
patient’s home, what distance have they travelled?
3. If someone is having a heart attack and must
make it to the hospital in 30 minutes, what is the furthest distance the crew
can travel and still arrive back at the hospital 30 minutes after the call is
made?
4. A second dispatch location is built in
Deerborn. Both stations cover the areas previously serviced by Station 42 and
take their patients to the hospital located beside Station 42. Describe how
this would change the original graph. (When a call comes in, emergency crews
leave from a dispatch location.)
Scenario
2 – Surf’s Up
A weather reporter
makes predictions based on data collected by the National Weather Centre. These
predictions can be very important to different people and professions. For
instance, the wind speed has a direct effect on the height of waves in the
ocean where many fishermen (anglers) work everyday. It could also be of
importance to a ferry boat company taking people to the 1000 Islands near
Kingston, or for parents planning a fishing trip with their children.
The data below is an example of the monthly averages for the speed of
peak gusts on Iles de la Madeleine in Quebec between 1984 and 1993. Create a
scatter plot showing the relationship between the month and the mean peak gusts
(knots). (*A gust is a quick burst of wind; the peak gust would be the maximum
speed it reaches in that burst.)
|
Months |
Mean (average) Peak Gusts
(knots) |
|
1 – January |
59 |
|
2 – February |
52 |
|
3 – March |
48 |
|
4 – April |
46 |
|
5 – May |
42 |
|
6 – June |
41 |
|
7 – July |
41 |
|
8 – August |
42 |
|
9 – September |
44 |
|
10 – October |
48 |
|
11 – November |
56 |
|
12 – December |
57 |
Using your graph,
answer the following:
1. Which month(s) have the lowest average peak
gust speeds?
2. Which month has the highest average peak gust
speeds?
3. Any gusts of wind with speed greater than 50
knots can be dangerous to small crafts. Draw a line on your graph showing this
speed. State all months with average peak gusts greater than 50 knots.
4. If it was discovered that November’s average
peak gusts were 5 knots below the mean this year, would you, as a fisherman, go
out on the lake and do some late season fishing? Justify your response.
Scenario
3 – Gas it Up!
A consumer activist
group wants the government to regulate gas prices. They investigated a 10-week
period, looking at the price of gas each Monday. They discovered that gas had
been going up by 1.0% each week. In the first week, gas was $0.65/L. Assuming
the price of gas continued to increase at this rate, create a scatter plot
showing the relationship between the week and the cost of gas per litre, over
the 10-week period.
|
Week Number |
Price per Litre of Gas |
|
1 |
0.65000 |
|
2 |
0.65650 |
|
3 |
0.66307 |
|
4 |
0.66970 |
|
5 |
0.67639 |
|
6 |
0.68316 |
|
7 |
0.68999 |
|
8 |
0.69689 |
|
9 |
0.70386 |
|
10 |
0.71090 |
Using your graph, answer the following:
1. Assuming the price keeps
rising at this rate, determine when gas will cost $1.00/L.
2. In week 8, John needs fuel. If
his tank is empty and can hold 50L, how much will it cost him?
3. A tour group planner creates a budget for a
bus trip to Stratford to see a play. They plan on
spending $100 on fuel for the bus. If the bus requires 75L for a one-way trip
to Stratford, what is the most expensive price per litre they can pay for gas
and still stay within their budget?
4. If they want to take the trip in the 8th
week, can the tour group stay within their budget? Explain.
As this is the first
activity of the unit, a teacher may want to discuss the solutions with the
class rather than collect the work. This early stage is a good chance to
provide diagnostic assessment. Student responses could be informally assessed
for Knowledge/Understanding, Application, and Communication to provide the
teacher with an idea of students’ background knowledge.
However, if the
teacher collects student work, the worksheet could be assessed for
Knowledge/Understanding, Communication, Application, and Problem Solving:
·
In Scenario 1,
Questions 1 and 2 focus on knowledge of the basic concepts, while Questions 3
and 4 require students to problem solve with linear equations as well as to
communicate their responses.
·
In Scenario 2,
Questions 1 – 3 demonstrate students’ understanding of the concepts and
properties of quadratic graphs, while Question 4 asks students to communicate
and reason an answer based on the model given.
·
In Scenario 3,
Question 1 focuses on students’ skills in extrapolation
(Knowledge/Understanding), Question focuses on application, while Questions 3
and 4 focus on problem solving situations requiring students to make a series
of choices.
The teacher may wish to create a rubric to mark the communication and
application questions in the worksheet. It may be easier to assess the
knowledge using a more traditional marking scheme.
Students’ skills in
using the graphing technology may vary. It may be appropriate to pair or group
students accordingly, as the focus of the investigation should be on the
discovery of the mathematical models.
Environment
Canada Website – http://weatheroffice.ec.gc.ca/index_e.shtml
OAME/OMCA “CARE
Package” (download) – http://www.oame.on.ca
Time: 2.5 hours
Students gather data
on the effect of layers of tinting on light intensity. Graphs are created and
students interpolate and extrapolate data from the graphs. Connections are made
to the tinting on vehicle windows and windows on buildings. Further connections
can be made to the change in light intensity with water depth.
Strand(s): Analysis of Mathematical Models
Overall
Expectations
MMV.01 - interpret
and analyse given graphical models;
MMV.03 - interpret
and analyse data given in a variety of forms.
Specific
Expectations
MM1.01 - interpret a
given linear, quadratic, or exponential graph to answer questions, using
language and units appropriate to the context from which the graph was drawn;
MM1.03 - make and
justify a decision or prediction and discuss trends based on a given graph;
MM1.05 - communicate
the results of an analysis orally, in a written report, and graphically;
MM3.04 - enter data
or a formula into a graphing calculator and retrieve other forms of the model.
·
entering and
graphing data using a graphing calculator.
·
Obtain tinted
plexiglas (MIRA’s will work) or coloured acetates and an incandescent light
source.
·
Students need
graphing calculator, light sensor, Computer-based laboratory (CBL) and program
for gathering light, or a CBL 2. Groups could take turns if only one is
available or the teacher could do a demonstration and have students transfer
data onto their own calculators.
Teacher
Facilitation
Introduce the
activity with a discussion about the various uses and issues around window
tinting.
·
Tinting is used
on car windows to reduce glare.
·
Many
provinces/states have regulations about the degree of tinting allowed on
vehicle windows.
·
Studies have
shown that drivers of vehicles equipped with tinted windows were more likely to
engage in aggressive driving than other drivers.
·
Tinting is used
on office windows to keep some of the sunlight out in order to reduce air conditioning
costs in the summer.
Students work
in groups to gather data for Part 1, or complete it as a demonstration and then
share data with their peers.
Tips
for setting up the demonstration:
·
Use an
incandescent light bulb.
·
Use the DataMate
program with the CBL 2 (preferable) or use the BULB program with the CBL.
·
For help with the
DataMate program, refer to Resources.
·
The instructions
on the BULB program are written for
gathering light data at changing distances; students should ignore these
instructions and instead add layers of “tinting” after each reading.
·
The BULB program gathers more data than
necessary. The teacher or students should remove the extra data after the
experiment is performed (i.e. you will likely only use five layers of “tinting”
but the program will take 11 readings; the last six readings should be
deleted).
Students could work in groups to analyse the model and then present
their solutions to the class on an overhead. If groups come up with different
models they can be compared.
Part 1: Gathering Data
Students:
·
turn the class
lights off and turn on the light source (preferably a single light bulb);
·
make the
appropriate connections between the light sensor, the CBL or CBL 2, and the
calculator;
·
start the program
to read light intensity;
·
place the light
sensor at a fixed distance (about 1–2 m) from the light source;
·
make a prediction
about the change that will occur as each layer is added;
·
place an
increasing number of layers of tinted plexiglas directly in front of the light
SENSOR and measure the light intensity;
·
graph the data
and make a prediction about whether an exponential, quadratic, or linear model
would be best;
·
determine an
appropriate model for the data (i.e., linear, exponential, quadratic) using the
regression feature of your calculator or by “guess and check”.
Part 2: Analysing Data
1. In one province, the law states that any
tinting on the side or rear windows of a vehicle must have a light
transmittance of 35% or more. Using your model, how many layers of the tinting
you examined would be acceptable under this law?
2. A construction company building an office has
been requested to tint the windows to lower air conditioning costs. If the
tinting applied reduces light in the same way as your tinting, how many layers
would be required to reduce light transmittance by 40%? by 65%?
Part 3: Making Connections
In the ocean, light
intensity decreases with depth following a similar model to the tinting model.
The “layers” of water act like layers of tinting. The table below shows data
for the per cent of light transmitted at various depths of the ocean on a sunny
day.
|
Depth (m) |
% of Light Transmitted |
|
0 |
100 |
|
75 |
90 |
|
150 |
81 |
|
225 |
72.9 |
|
300 |
65.6 |
|
375 |
59 |
1. Graph this data and compare the graph to your
graph from Part 1. How are they the same? How are they different?
2. At approximately what depth would there only
be 5% of light transmitted? Note: you will need to change the WINDOW of your
graph to extrapolate these values.
3. If a certain species of fish requires at least
50% light transmitted, what would be the greatest depth it could live in?
4. If a certain species of fish does not respond
well to more than 40% light transmittance, what depth of water should it live
in?
5. Who might find this data useful? Give examples
of people who could use this information either in their jobs or in their lives
outside of their jobs.
Teacher
Facilitation
Assist students in
making the connection between tinting and the changes in light intensity at
various depths of the ocean. Other applications may include:
·
creating
environments with appropriate lighting for various fish species in large-scale
aquariums;
·
scuba diving.
Parts 1 and 2 could
be completed as a class or in groups and taken up by the teacher or students.
Individual reports for Part 3 can be submitted and assessed.
·
Assess
Application based on the student’s ability to apply the model to answer
Questions 2, 3, and 4.
·
Assess
Communication based on the student’s answers to Questions 1 and 5.
Websites
San Jose
University – http://geosun1.sjsu.edu/~dreed/105/exped7/13.html
(Provides data on changing light intensity with water depth.)
NC State University
– http://www.ncsu.edu/sciencejunction/route/usetech/index.html
(Provides instructions for using the CBL 2.)
Print
Brueningsen,
C., B. Bower, L. Antinone, and E. Brueningsen-Kerner. Real-World Math with the CBL System: Activities for the TI-83 and TI-83
Plus. Texas: Texas Instruments Incorporated, 1999.
ISBN 1-886309-28-0
Randall, Jack. Sensor Sensibility. Berkeley: Key
Curriculum Press, 1997. ISBN 1559532874
Time: 1.25 hours
Students examine CPI
(Consumer Price Index), including how it is calculated and its use in measuring
inflation. Inflation rates are used to compare prices and salaries from various
time periods.
Strand(s): Applications of Statistics, Analysis of Mathematical Models
Overall
Expectations
MMV.01 - interpret
and analyse given graphical models;
MMV.02 - interpret
and analyse given formulaic models;
ASV.04 - evaluate
the validity of the use of statistics in the media.
Specific
Expectations
MM1.01 - interpret a
given linear, quadratic, or exponential graph to answer questions, using
language and units appropriate to the context from which the graph was drawn;
MM1.03 - make and
justify a decision or prediction and discuss trends based on a given graph;
MM2.01 - evaluate
any variable in a given formula drawn from an application by substituting into
the formula and using the appropriate order of operations on a scientific
calculator;
AS4.03 - explain the
meaning and the use in the media, of indices based on surveys.
·
use of compound
interest formula to calculate A;
·
enter and graph
data using a graphing calculator.
·
Prepare a review
of the compound interest formula.
Teacher
Facilitation
·
Discuss how the
Consumer Price Index (CPI) is a measure of the rate of price change for goods
and services bought by Canadian consumers.
·
Explain how it is
obtained by comparing, through time, the cost of a fixed basket of goods and
services.
·
CPI is used to
determine increases in Old Age Security pensions, CPP payments, other social
and welfare payments, spousal and child support payments, and wage increases.
Your uncle tells you “…back in 1971, when I was
a kid, it only cost me $1.50 to go see a movie.” The cost seems pretty cheap
compared to today’s prices. The chart contains CPI data for the years 1971
to 1980.
|
Year |
CPI for All Items |
% Change from Previous Year (round to 1 decimal place) |
|
1971 |
24.9 |
> |
|
1972 |
26.1 |
|
|
1973 |
28.1 |
> |
|
1974 |
31.1 |
|
|
1975 |
34.5 |
> |
|
1976 |
37.1 |
|
|
1977 |
40.0 |
> |
|
1978 |
43.6 |
|
|
1979 |
47.6 |
> |
|
1980 |
52.4 |
1. Create a scatter plot of the data, CPI vs
Year, on a graphing calculator.
2. Examine your graph and make a prediction
about the type of growth this appears to be. Linear, quadratic, exponential?
How do you know?
3. Complete the % Change column (e.g., % change
= (CPI for 1972 – CPI for 1971)/(CPI for 1971)).
4. Find the average percentage increase in
prices over these years.
5. Assume the prices continue to increase at the
same rate and use this rate as an approximate rate of inflation for the price
of goods in Canada. Use this value to calculate what the $1.50 movie should
cost now. Use the compound interest formula to help you.
A = P(1 + i)n
in this case:
A – is the new price
P – was the price in 1971
i – is the average annual inflation rate
n – is the number of years
6. How does your answer from Question 5 compare
to the current price of movies? Based on this data, does the current price seem
reasonable?
7. In this example, we used an average inflation
rate based on the years 1971 to 1980. Why might this give us an inaccurate
picture of inflation?
8. Using CPI data from 1971 to
2000, an average annual inflation rate of 5.4% was calculated.
a) Use this average to calculate what the cost of a movie should be today. How does this value compare to the actual price?
b) Assuming this inflation rate remains the same, what will the price of a movie be in 10 years? 20 years?
Extension 1
Choose a profession and investigate the increase in income in this profession for past years. Make a comparison between the rate of increase of wages with the rate of increase of CPI. Write a report to summarize your findings and offer possible explanations for any differences in the rates.
Problem: Suppose that your parents saved $30/month for your college education, beginning in the month you were born. An investment counsellor has managed to earn about $5,000 interest in total with that money over the last 17 years. This year it costs about $4,000/year to attend your local college; this covers tuition and books. You are planning on starting college next year. You have heard that inflation will be 5.6 % per year. If so will you have enough money to pay for your college education? State any assumptions you are making when working with this problem.
Extension 2
Students investigate
college fees over the last decade and make predictions for the future, i.e.,
What will tuition for their children be?
·
The college
funding problem could be used as a performance task and assessed for
Application, Thinking/Inquiry/Problem Solving, and Communication.
·
Use Rubric
(Appendix A – Rubric for Evaluation of Report on Wage Increases) to assess
Thinking/Inquiry/Problem Solving and Communication for Extension 1.
·
Provide
scaffolding for the problem and extension.
·
Allow students to
present their reports orally.
Websites
Bank of
Canada – http://www.bank-banque-canada.ca/en/inflation_calc.htm (An inflation
calculator which uses CPI)
Canadian Council on
Social Development – www.ccsd.ca/fs_avgin.html (Income data for Canada)
Statistics Canada –
www.statcan.ca (Income data)
Time: 1.25 hours
Students find the roots of quadratics using the graph and its table of
values. Using the data from the graph, students make decisions based on trends
they discover.
Strand(s): Analysis of Mathematical Models
Overall
Expectations
MMV.01 - interpret and analyse given graphical models;
MMV.03 - interpret
and analyse data given in a variety of forms.
Specific
Expectations
MM1.01 - interpret a
given linear, quadratic, or exponential graph to answer questions, using
language and units appropriate to the context from which the graph was drawn;
MM1.03 - make and
justify a decision or prediction and discuss trends based on a given graph;
MM1.04 - describe
the effect on a given graph of new information about the circumstances
represented by the graph (e.g., describe the effect of a significant change in
population on a graph representing the size of the population over time);
MM3.04 - enter data
or a formula into a graphing calculator and retrieve other forms of the model
(e.g., enter data and retrieve a scatter graph or a table of values; enter a
formula and retrieve a table of values or the graph of a function).
·
use of graphing
technology to graph equations, trace graphs, and read tables;
·
given the vertex
form of the equation, identify the vertex.
·
Students should
briefly review the vertex form of an equation.
·
Have a class set
of calculators available for this lesson.
Students work through the activity to discover the meaning of roots in a practical problem.
Teacher
Facilitation
·
Review
definitions of Grade 10 concepts. Students review their knowledge of terms,
such as x-intercept, root, vertex,
quadratic, etc. Students need these terms to complete the worksheet.
·
Some students
need more direction from the teacher than others, but the teacher should allow
students to work independently first, as this is an important skill they will
need in college or the workforce they intend to enter.
·
Class work should
include problems that ask students to graph (using technology) different
problems. They should identify the roots to answer specific questions for each
problem. Homework should include situations where the graphs are given so that
students can complete these questions without technology.
Sample Worksheet
In many urban centres, the population is
growing rapidly. As a result, more and more homes are being built. Builders
create subdivisions in the neighbourhood. The hydro company provides the
builder with a layout of the poles needed to hang the electrical wires. The
builder uses the poles to provide temporary electricity to each home during the
building process.
In one subdivision
in Oakville, the following equation was created to model how the wire must hang
between two hydro poles.
Note: y = amount of dip (distance below the
horizontal)
x
= location of pole
origin is at the first pole

Problem: How
far apart are the two poles? Follow the directions to solve the problem.
1. To answer this question we would like to know
the position of the second pole. That distance will indicate how far apart any
two poles should be. The value we are trying to find is called a
<<root>> (students fill in the blank).
2. Using your graphing calculator, graph the
equation.
3. Using the TRACE feature, find the position of
the second pole. What point(s) are you looking for on your graph? <<x-intercepts>>.
4. Another way to find the root is to use the
TABLE feature and look for a y-value
of <<zero>>.
5. What is the vertex of the equation? <<(p, q) from the equation in y = a
(x-p)2 + q. from>>
6. Identify the relationship between the
distance between the poles and the vertex. Explain your findings. <<(5,
2) where 5 is half the distance between two poles and 2 is the depth of the
dip>>.
7. This Oakville subdivision has a street that
is 210 m long. How many posts would you place on the street? Assume the depth
of the “dip” between poles is similar to the model.
8. Given the following guidelines:
· Poles cannot be more than 12 m apart and no less than 8 m apart.
· The depth of the dip cannot be more than 2.5 m and must not be taut (straight across).
Create a quadratic equation to model the positioning of poles on a street that is 115 m long.
The teacher could
use the activity for diagnostic assessment of students’ knowledge of quadratics
and their ability to apply those concepts to different scenarios. Use a similar
activity to evaluate students but use this as an opportunity to provide helpful
feedback, using the following guidelines:
·
Questions 1–5 are
knowledge based, helping students discover the real-life application of the
roots of an equation. Question 7 is an application that asks students to work
with the given equation and find a solution to practical problems. Questions 6
and 8 assess Thinking/Inquiry/Problem Solving because they require students to
make a series of choices and/or provide reasoning in their answers.
·
Pair students in
ESL/ELD courses with students who have strong language skills for interpreting
some of the more complicated questions.
Time: 1.25 hours
Students use
graphing calculators to create scatter plots and equations of speed vs.
stopping distances on wet pavement. Students predict equations of graphs for
other surfaces (dry pavement, gravel, packed snow, and ice).
Strand(s): Analysis of Mathematical Models
Overall
Expectations
MMV.01 - interpret
and analyse graphical models;
MMV.03 - interpret
and analyse data given in a variety of forms.
Specific
Expectations
MM3.04 - enter data
or a formula into a graphing calculator and retrieve other forms of the model;
MM1.03 - make and
justify a decision or prediction and discuss trends based on a given graph;
MM1.04 - describe
the effect on a given graph of new information about the circumstances
represented by the graph.
·
use of graphing
calculators to create scatter plots;
·
use of regression
features on graphing calculators.
·
Graphing
calculators are required for each student (for writing and estimation of
equations, it would be best to have the decimal point set to two places).
Part 1 – Wet
Pavement
When the police
arrive at the scene of a collision, they can make deductions about the speed of
the vehicle from the length of the vehicle’s skid marks. Use the following data
for stopping distances vs. speeds on wet pavement:
|
Speed (km/h) |
48 |
64 |
80 |
96 |
112 |
|
Stopping Distance (m) on Wet Pavement |
51 |
76 |
116 |
169 |
231 |
1. Create a scatter plot for stopping distances
vs. speeds on wet pavement.
2. Using a differences chart to help you, guess
an equation for a curve of best fit. Test your guess on the calculator.
3. Perform various regressions (linear,
quadratic, exponential) for this data. Which regression appears to best fit the
data? Use this regression to determine the equation of the curve of best fit.
How does it compare to your guess in Question 2?
4. Using the trace function, obtain an estimated
speed of a vehicle with a stopping distance
of 100 m, 216 m, and 300 m on wet pavement.
5. Use the equation to find the “exact” speed of
a vehicle with a stopping distance of 100 m, 216 m,
and 300m on wet pavement.
6. Why is your answer to Question 5 not really
exact? <<An equation is an “exact” answer only if the algebraic model is
exact>>.
Part 2 – Predicting
Distances on Dry Surfaces
1. Describe how the stopping distances will
change if the surface is gravel? Dry pavement?
2. Predict the stopping distances for the same
vehicle on dry pavement.
|
Speed (km/h) |
48 |
64 |
80 |
96 |
112 |
|
Stopping Distance (m) on Dry Pavement |
|
|
|
|
|
(Note: actual distances given below are
not intended to be on the worksheet. Questions 1 and 2 could be discussed and
then display actual distances for students to make comparisons.)
|
Speed (km/h) |
48 |
64 |
80 |
96 |
112 |
|
Stopping
Distance (m) on Dry Pavement |
31 |
48 |
75 |
113 |
171 |
3. Create a scatter plot for stopping distances
vs. speeds on dry pavement.
4. What model do you think would best fit this
data?
5. Test several models by performing regressions
for the data. Choose the best model and record the equation, explaining why
that model is best.
Part 3 – Predicting
the Equation for an Icy Surface
1. Graph the two equations from Part 1 and Part
2 simultaneously on the graphing calculator.
2. Compare the two graphs and describe the
similarities and differences.
3. Compare the two equations and describe their
similarities and differences.
4. Predict how the graph of stopping distances
vs. speeds on icy surfaces will look compared to the previous two graphs.
5. Predict the equation for stopping distances
vs. speeds on icy surfaces. Explain your reasoning.
6. Graph your predicted equation using the
graphing calculator.
7. Determine the actual equation for stopping
distances vs. speeds on icy surfaces using the following data:
|
Speed (km/h) |
48 |
64 |
80 |
96 |
112 |
|
Stopping
Distance (m) on Icy Surfaces |
135 |
223 |
372 |
553 |
818 |
8. Graph the predicted and actual curves together.
9. Compare your prediction with the actual curve.
Part 4 – Class
Discussion
1. In order for police to use this data, what
assumptions have been made?
Discuss such items as size and mass of vehicle, condition of vehicle, number of passengers, type of tires on vehicle, driver competence, ABS brakes.
2. Why is the data unreasonable?
Discuss that it would be tough to create a 300-m-long skid mark and the fact that it would be tough to keep a skidding car straight for that long.
Application and
Communication could be assessed by having students complete Part A, Part B, or
both Parts A and B.
·
Part A – Students
predict their own data for the graph of stopping distances vs. speeds on packed
snow. Students then create a scatter plot on graph paper and perform a
quadratic regression on their data.
·
Part B – Students
use the data to create a scatter plot, perform a quadratic regression, and
describe their confidence in the quadratic model.
|
Speed (km/h) |
48 |
64 |
80 |
96 |
112 |
|
Stopping
Distance (m) on Packed Snow |
62 |
96 |
164 |
243 |
370 |
·
Students could
work in partners to assist each other.
Flagging
Instructions (stopping distances)
– www.dot.ca.gov/hq/traffops/signtech/signdel/flagging/stopping.htm
Time: 2.5 hours
Students create
graphs from a given quadratic equation. They then look for a way to find the
roots algebraically. This will lead to factoring equations of the form ax2 + bx + c = 0. After
determining the roots, students analyse the equation and make
decisions/conclusions.
Strand(s): Analysis of Mathematical Models
Overall
Expectations
MMV.01 - interpret
and analyse given graphical models;
MMV.02 - interpret
and analyse given formulaic models;
MMV.03 - interpret
and analyse data given in a variety of forms.
Specific
Expectations
MM1.05 - communicate
the results of an analysis orally, in a written report, and graphically;
MM2.06 - factor
expressions of the form ax2
+ bx + c;
MM2.07 - solve
quadratic equations by factoring;
MM3.04 - enter data
or a formula into a graphing calculator and retrieve other forms of the model
(e.g., enter data and retrieve a scatter graph or a table of values; enter a
formula and retrieve a table of values or the graph of a function).
·
factoring
expressions of the form ax2
+ bx + c;
·
solve simple linear
equations (3x – 5 = 0).
·
Student will
learn how to factor quadratics of the form ax2
+ bx + c to find roots. Review Grade 10 factoring techniques and solving
of quadratic equations of the form 0 = ax2
+ bx + c.
Students:
·
graph a quadratic
function on graphing technology to identify the roots of the corresponding
equation;
·
identify the
roots by factoring equations in the form ax2
+ bx + c = 0;
·
interpret the
roots to answer questions based on the given equation.
Teacher
Facilitation
Day 1
·
Begin with a
review of finding roots of a simple trinomial using the following example:
Sarah is watching her younger sister play with her friends outside. They are skipping. They have one end of a rope tied to a tree and the other is held by one of the girls. The rope appears to hang in a parabolic shape. The height of the rope, with a horizontal axis occurring where the rope is tied/held, m metres from a “spotter,” is closely modelled by the quadratic equation: h = m2 – 6m + 5. Determine the position of the two ends of the rope (i.e., h = 0).
·
Present students
with the following problem (on an overhead):
A golfer, standing on an elevation 12 m above the hole, hits a ball into the air. The height of the ball in metres is given by h = -5t2 + 17t + 12 where t is the number of seconds after it is hit. When does the ball reach the ground (h = 0m)?
Create a graph of the function. What special point(s) on the graph identifies the time when the ball reaches the ground? Describe how you came to that conclusion.
Is it always necessary to graph the function in order to find the roots? What might be some disadvantages to using a graph?
·
Take the equation
from the golfing scenario and use it to develop a lesson around factoring using
decomposition (the teacher may also want to introduce other methods of
factoring to accommodate different learning styles.)
·
Once you have the
factored form, you need to talk about how to SOLVE for the ROOTS. Once roots
are determined you can analyse the graph (e.g., to solve (5t + 3)(t – 4) = 0, solve
both 5t + 3 = 0 and
t – 4 = 0 to find the two answers for
t). Students now reason to determine
the time when the ball hits the ground.)
·
Follow-up with
examples out of context to consolidate the concept (e.g., solve 3x2 -17x + 10 = 0).
·
Provide students
with factoring “drill” type questions from their textbooks for homework.
Day
2
·
Students work
through a practical example and then present or discuss their solutions.
Example: A specialty ice cream shop sells their 2-L ice cream pails for $7. They have decided to drop the price in an attempt to increase sales. The equation P = -5x2 + 23x + 84, where P represents the Profit made in one week on the pails and x represents the number of $1 decreases, models this situation. If the company wants to make $108 profit on their ice cream pails during the next week, how much should they sell the pails for?
·
Homework/class
work on Day 2 may contain some out of context solving of questions but should
FOCUS on problems within a context. (Students have practised the concept of
factoring and should apply it to solve a practical problem.)
·
A quiz on
factoring to assess Knowledge would be beneficial to students after they have
had an opportunity to practise this new skill.
·
As this is the
last day for quadratic models, it may be appropriate to have a short open-book
formative assessment. It would be a good opportunity to provide students with
feedback on the skills they have developed and those they need to practise
before the summative assessment activity. You may want to use the sample
question below.
Parks and Recreation crews are setting up rectangular skating rinks for
the city of Ottawa. The length of a skating rink should be twice the width less
5 m. The equation they use to model this situation is:
A = 2w2 – 5w, where
A is the area of the rink and w is the width in metres.
1. Create a graphical model of
this equation on your graphing calculator.
2. Using your graph, if the width
of the rink is 4 m, what is the approximate area?
3. For the rink in Question 2,
what is its approximate length?
4. Using your graph, if they want
an area of 150 m2 what is the approximate width of the rink?
5. Verify your answer to Question 4 algebraically
to determine the exact width of a rink with an area
of 150 m2.
Time: 2.5 hours
Students plan a trip
that visits four professional sports teams’ cities in seven days. Students
collect information from various charts and plan the trip within a given
budget.
Strand(s): Analysis of Mathematical Models
Overall
Expectations
MMV.03 - interpret
and analyse data given in a variety of forms.
Specific
Expectations
MM3.01 - retrieve information
from various sources;
MM3.02 - identify
options that meet certain criteria, using more than one chart, spreadsheet, or
schedule;
MM3.03 - make
informed decisions, using data provided in chart, spreadsheet, or schedule
format and taking into account personal needs and preferences.
·
interpolation and
extrapolation.
·
Use the Internet
to obtain team schedules for a sport and to obtain flight schedules.
Students:
·
plan a trip that
goes to games of sports teams (e.g., hockey, basketball, etc.) in four
different cities.
·
stay within a
budget.
Teacher
Facilitation
·
Prepare for
students to collect the information regarding games and flights from the
Internet or have pre-printed data available for them.
·
Brainstorm how
much time is really spent when you take a plane – arriving at the airport
early, etc.
·
Have each student
create a Trip Plan (see sample worksheet), which indicates which cities they
will attend in the chosen order.
·
Students must
make sure that their flights arrive three hours prior to the start of a game so
they can get from the airport to the arena and pick up their tickets. [Tickets
are prepaid.]
·
Students must be
given a budget (make note of current costs).
·
Teachers may opt
to include hotel accommodations in the process. This may be done through a
random draw for each city they stay in.
·
Teachers may
choose to make a game of it and find the student: Who travels the most km?, Who
completes the trip on the smallest budget?, Who completes the trip in the least
number of days?, etc.
·
This activity is
a fantasy trip and should be presented that way. If the teacher is concerned
that the high costs involved in the “trip” are inappropriate for the class,
they may choose a smaller version of the activity. This could include arranging
bus/train schedules to watch OHL hockey teams play in various cities in
Ontario. Their budget could be the money collected in a school fundraiser.
·
Another way to
“hide” costs would be to have the Local Radio station sponsor the trip as a
contest prize. The budget would be a set donation from a sponsor – students
could then be told to see as many games as the schedule and budget will allow
during a seven-day period. (Students who can plan a trip to see the most games
win a prize!)
Sample Worksheet
Your mission should
you choose to accept it…
You and a friend
must travel to four different cities to watch <<your favourite
sport>>. Each time you will watch a different team play in their
hometown. You must complete this mission on a budget of <<$$$$$>>.
You must arrange flights between each city you travel to and make sure that you
arrive at least three hours before the start of the game you wish to attend.
You can stay overnight in any city, for any number of nights, but you must
return home within seven days of departure.
Collecting Information
1. Determine the following, given the game
schedule you have found/been given.
|
Game |
City/Team |
Date/Time of Game |
Airport |
|
1 |
|
|
|
|
2 |
|
|
|
|
3 |
|
|
|
|
4 |
|
|
|
2. Find flights that will connect you from home
to your first city and then to each city after that, remembering to return home
no later than seven days after your first flight.
|
Departure City |
Departure Time |
Arrival City |
Arrival Time |
Cost |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
3. Given a list of ticket prices for each team
in the league, determine the cost for you and your friend to attend each of the
games you have chosen.
|
Game |
Cost for Two Tickets |
|
|
|
|
|
|
|
|
|
|
|
|
4. Determine the total length of time in days
for your trip.
5. Determine the total cost of your trip.
6. Determine the average cost per day for your
trip.
7. Write a summary of the trip
given in a day-by-day outline.
8. What factors affected your decisions in
choosing cities to visit? Explain.
9. If you could have one of: more money or more
time, which would make the mission easier and why?
The purpose of this
activity is to assess students’ ability to make connections based on given
criteria using more than one chart or spreadsheet. Question 7 could be assessed
under Thinking/Inquiry and Problem Solving, as students must make choices of
cities and flights that must be correctly sequenced to fit the criteria.
Questions 8 and 9 could assess Communication and Reasoning. A partial rubric is
provided (see Appendix B – Sports Fantasy Trip Rubric).
·
This activity may
be of difficulty for students who are new to the country or who do not follow
professional sports. You may wish to create a sequence of cities that students
must travel between in a given timeframe to simplify the problem (i.e., you
could change the scenario to “following a band” to watch concerts in different
cities).
·
For students who
have difficulty processing several items at one time, it might be better if they
could print the Internet information or receive hard copies to work from.
·
Explain the
entire project orally, and provide chunking suggestions and intermediate
deadlines. If student has difficulty at any point, provide support so they may
continue on, so they will not give up.
Air Canada –
www.aircanada.ca (for flight information)
Official
Website of MLB – www.mlb.com (contains schedules by month or team)
Official
Website of the NBA – www.nba.com (contains schedules by month or team)
Official Website
of the NHL – www.nhl.com (contains schedules by month or team)
Ontario Hockey
League – www.ontariohockeyleague.com (contains schedules by month or team)
Time: 2.5 hours
In this summative
activity, students develop formulas to determine the amount of materials
required for various deck sizes. They use quadratic and linear models, combined
with prices, to create a formula to determine the cost of various decks.
Strand(s): Analysis of Mathematical Models
Overall
Expectations
MMV.01 - interpret
and analyse given graphical models;
MMV.02 - interpret
and analyse given formulaic models;
MMV.03 - interpret
and analyse data given in a variety of forms.
Specific
Expectations
MM1.05 - communicate
the results of an analysis orally, in a written report, and graphically;
MM2.01 - evaluate
any variable in a given formula drawn from an application by substituting into
the formula and using the appropriate order of operations on a scientific
calculator;
MM2.02 - construct
formulas to solve multi-step problems in particular situations;
MM2.04 - judge the
reasonableness of answers to problems;
MM3.03 - make
informed decisions, using data provided in chart, spreadsheet, or schedule
format and taking into account personal needs and preferences;
MM3.04 - enter data
or a formula into a graphing calculator and retrieve other forms of the model
(e.g., enter data and retrieve a scatter graph or a table of values; enter a
formula and retrieve a table of values or the graph of a function).
·
Graphing
calculators are required for some parts of the assessment.
·
Diagrams of deck
parts and deck instructions – Appendix C.
·
Manipulatives
such as straws, cube-a-links, and popsicle sticks may be helpful to some
students.
Teacher
Facilitation
·
Set up the
problem: Students are starting their own business that sells do-it-yourself
deck systems. Clients can order a kit to build their own square deck in any
size (1 m × 1 m, 5 m × 5 m,
21 m × 21 m, etc.). Students develop methods for determining how many of each
piece they will need for each size deck and for calculating the total cost for
the customer.
·
Have students
work in groups at first to explore the problem.
·
Provide each group
with a copy of the page showing the deck pieces and the diagrams of 1 m x 1 m
and 4 m x 4 m decks.
·
Students may
benefit from having manipulatives available to help explore the problem.
In your
group:
1. Examine the deck parts and the diagrams
showing requirements for a 1 m × 1 m deck
and a 4 m x 4 m deck (see Appendix C – Deck Pieces and Diagrams).
2. Complete the chart to show the number of
parts required for each size deck (1 m × 1 m
up to 5 m × 5 m). You may want to draw diagrams for the other sizes.
|
Size |
Base Piece |
Support Board |
Surface Board |
End Board |
|
1m × 1m |
|
|
|
|
|
2m × 2m |
|
|
|
|
|
3m × 3m |
|
|
|
|
|
4m × 4m |
|
|
|
|
|
5m × 5m |
|
|
|
|
|
|
|
|
|
|
|
n × n |
|
|
|
|
On your own:
3. Try to develop a formula that you could use
to calculate how many of each piece you would need for a square deck of any
size. You may want to use a graphing calculator to help you. Look for patterns
that indicate whether a linear, exponential, or quadratic model would work
best. Write the formula for each piece in the last row of the chart in Question
2.
4. The wholesale cost of each item is given in
the following chart. You will likely want to charge your clients more for each
piece so that you will make a profit. Decide how much you will mark up your
prices and calculate what you will charge your clients for each piece.
Percentage Mark-up = %
|
|
Your Cost |
Client’s Price |
|
Base Piece |
$5.70 |
|
|
Support Board |
$3.20 |
|
|
Surface Board |
$9.70 |
|
|
End Board |
$3.75 |
|
5. Using your prices above, calculate the cost
of a 2 m × 2 m deck. Show your work.
6. Thinking about how you calculated the cost in
Question 5, create a formula that you could use to calculate the cost of any
size deck.
7. A client wants to purchase a system to build
an 8 m × 8 m deck. Calculate what you will charge him. Show your work.
8. If a client has $2000 to spend, what size
deck could they get? Show your work.
9. You also recommend that your clients apply
two layers of stain to their deck. A can of stain
costs $18.00 and covers 18m2 with one coat. How will you factor this
into your formula?
10. Create an instruction sheet to help someone
working for your company. The instruction sheet should explain how to calculate
the cost of any size deck.
·
Problem solving
can be assessed as students explore the problem, develop a model for the number
of each piece required, and manipulate the models to create a cost formula.
·
Application can
be assessed in students’ ability to use their formula to answer Questions 6-8.
·
Communication can
be assessed in the clarity of the instructions to calculate the cost of any
size deck.
·
Allow students to
present their instructions orally to the teacher.
·
Provide
manipulatives so students can visualize the problem.
·
Provide
additional scaffolding (such as structured worksheets) to help students break
the problem down further.
|
Criteria |
Level 1 (50-59%) |
Level 2 (60-69%) |
Level 3 (70-79%) |
Level 4 (80-100%) |
|
Problem Solving - collection of data - forming a model - making conclusions and comparisons |
- gathers limited relevant data on income - creates a model that has limited effectiveness - makes conclusions and comparisons with limited effectiveness |
- gathers some relevant data on income - creates a model that is somewhat effective - makes conclusions and comparisons with some effectiveness |
- gathers generally relevant data on income - creates a model that is generally effective - makes conclusions and comparisons with considerable effectiveness |
- gathers consistently relevant data on income - creates a model that is thorough and effective - makes conclusions and comparisons with high degree of effectiveness |
|
Communication - integration of mathematical forms with narrative - clarity in explanations and justifications |
- limited use of correct mathematical forms - explanations and justifications have limited clarity |
- some use of correct mathematical forms - explanations and justifications have some clarity |
- most often uses correct mathematical forms - explanations and justifications have considerable clarity |
- consistently uses correct mathematical forms - explanations and justifications are consistently clear |
Note: A student whose achievement is below Level 1 (50%) has not met the
expectations for this assignment or activity.
|
Criteria |
Level 1 (50-59%) |
Level 2 (60-69%) |
Level 3 (70-79%) |
Level 4 (80-100%) |
|
Communication - clarity in explanations and justifications of choices |
- explanations and justifications have limited clarity |
- explanations and justifications have some clarity |
- explanations and justifications have considerable clarity |
- explanations and justifications are consistently clear |
|
Problem Solving - collection of data - understanding the problem to make realistic timelines |
- gathers limited appropriate data on trip costs - timelines created demonstrate limited understanding of the problem |
- gathers some appropriate data on trip costs - timelines created demonstrate some understanding of the problem |
- gathers considerable appropriate data on trip costs - timelines created demonstrate general understanding of the problem |
- gathers consistently appropriate data on trip costs - timelines created demonstrate thorough understanding of the problem |
Note: A student whose achievement is below Level 1 (50%) has not met the
expectations for this assignment or activity.
Deck Pieces

Diagram and
Instructions for a Basic 1 m × 1 m Deck

·
Secure four base
pieces into the ground.
·
Attach one
support board across every two bases as shown.
·
Attach surface
board on top of support boards.
·
Attach end pieces
at either end (perpendicular to support boards).
Diagram and
Instructions for a Basic 4 m × 4 m Deck

·
Secure nine base
pieces into the ground.
·
Attach one
support board across every two bases as shown.
·
Attach one
surface board between every four base pieces.
·
Attach end
pieces.
Overview | Unit
3 | Course
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