Unit Rate/Constant of Proportionality Reteach

​Unit Rate/COP Reteach

By Christi Rankin

-I can find the unit rate involving complex fractions.
-I can create a model with functions to represent a proportional relationship in a real world situation.
-I can determine which function is represented by a given model.
-I can identify the constant of proportionality.
-I can determine which table, graph, or equation has a given constant of proportionality.

Unit Rate
I can find the unit rate involving complex fractions.

Lowry built 1/2 of a tower in 2 minutes. If he continues to build at that same rate, how long will it take him to build one tower?

Unit Rate
I can find the unit rate involving complex fractions.

G-Mama is using 4 cups of milk. How much cocoa mix should she use?

Unit Rate
I can find the unit rate involving complex fractions.

If Travis can wash 1/3 of his police car in 1/4 of an hour, what is his unit rate?

Discuss and solve with your partner.
Show your work on your white board and circle your answer.

Multiple Choice

Determine the unit rate of a marathon runner

who travels 5/2 miles in 1/4 hour.

• 10 mi/h

• 5/8 mi/h

• 11/4 mi/h

• 1/10 mi/h

How can you tell if the number of test questions is proportional to the numer of word problems? Think Time!

​Constant of Proportionality (K)

Proportional or Not?

​# of word problems	​# of test questions
​2	​18
​3	​27
​4	​34
​5	​50

Multiple Choice

Proportional or Non-Proportional?

• Proportional

• Non-Proportional

Multiple Choice

Proportional or Non-Proportional?

• Proportional

• Non-Proportional

Discuss with your partner: could you fill in the table correctly? how?

​Constant of Proportionality (K)

I can identify the constant of proportionality from a table and an equation.

y = 5x

​x	​y
​0	​
​1	​
​2	​
​3	​

Multiple Choice

Identify the constant of proportionality.

• 2

• 3

• 0.6

• 1.50

What would your first step be to answer this question? Think.
Then we will share.

​Constant of Proportionality (K)

Write an equation that represents the proportional relationship of total cost, x, to the number of students attending the trip, y, at a rate of $10 per student.

Multiple Choice

If Justin can type 408 words in 4 minutes at a constant rate, what is the constant of proportionality (K)?

• 4

• 102

• 120

• 408

Multiple Choice

If Justin can type 408 words in 4 minutes at a constant rate and K= 102, which equation represents the proportional relationship?

• y=4x

• x=4y

• y=102x

• x=102y

Let's discuss.

​Constant of Proportionality (K)

I can determine the constant of proportionality from a graph.

Multiple Choice

Using the graph, determine the constant of proportionality.

• k = 0
• k = 1
• k = 3
• k = 6

Multiple Choice

Is the graph proportional or non proportional?

• proportional
• non proportional