Constant Proportionality from Tables
Constant of Proportionality from Graphs
Constant of Proportionality from Words
Constant of Proportionality and Equations
Unit Rates/ Scales
100

Drew paints portraits.  Find the constant of proportionality if it is a proportional relationship 

Time (in hours) = x             Number of portraits = y

           1                                          5

           2                                          10

           3                                          15


5 portraits per hour

100

Does the graph below show a proportional relationship? How do you know?

Yes, because it forms a straight line through the origin and has a constant unit rate

100

Morgan bought 24 batteries packed in 6 equal packs. What is the unit rate per pack?

4 batteries per pack

100

Find the constant of proportionality: y = 7x

k = 7

100

4 In N Out Burgers contain 4/3 pounds of beef. Write an equation that shows the relationship between total pounds of beef and the number of burgers.

y=1/3 x

200

The table shows the amount earned by Harry for selling ice cream.  Find k.


Cups Sold = x              3          5        7         

Earnings ($)  = y         12        20      28       


CoP = 4

200

What is K with proper units?

k = 1.2 miles per hour

200


Julie brought 5 pounds of cans to a recycling place and was paid $2. Find the constant of proportionality (cost per pound)

$0.40/pound

200

Double points: 

Race to the Top—In Mario Kart 8, Wario can finish 5 laps in 1/4 hour. 

  1. Write an equation to represent the relationship between the number of laps and hours. 

  2. How many laps could Wario finish in 1.3 hours? 

1.   y = 20x

2.   26 laps

200

Determine the scale factor between the two drawings below:

1.5      or      1  1/2
300

Fred wrote notes during an exam.  Find the CoP (with correct units) if it is a proportional relationship.


Notes (pages)        8             9               10            11

Time (in hours)      18           19              20            21

It is not proportional, there is no CoP. 

300

Find the constant of proportionality with correct units

5 gallons per min

300

To make juice, Michael combines 4 liters of water and 12 scoops of juice mix. What is the CoP (scoops per liter)?

3 scoops per liter

300

Daisy made bread.  The equation B = 4f shows the number of breads basked based on the amount of flour used.  Where B is the number of bread loaves made and f is the cups of flour used.  Find the constant of proportionality.

k = 4 loaves per cup

300

Mr. V only eats vegetables. He buys 8 pounds of broccoli for $9.84. If Mr. K went to the same store and wants to buy 17 pounds of broccoli, how much would it cost him?   

$20.91

400

A ferry transports bikes to an island.  Write k (which is the CoP). 


Number of bikes (x)              10             12             14            

Number of trips (y)              5                6               7              

k = 0.5

400

Find k with proper units.

k = 3 gallons per minute

400

Zachary's time machine needs 14 megawatts of electricity to travel back 7 years.  What is the unit rate (megawatts per year)?

 2 megawatts per year

400

The number of milk bottles sold can be determined by the equation P = 0.35n, where P is the number of bottles of milk and n is the number of boxes opened.  Find the constant of proportionality with correct units.

k = 0.35 bottles per box

400

The blueprint for an apartment unit says that every 1 inch corresponds to 3 yards.  


What is the actual area of the bedroom? 

20.475 yd2

500

Alice bought comics.  Find the k (CoP with correct units) if the table shows a proportional relationship.


Number of comics             2             4             6            

Price (dollars)                   6            12            18           


k = 3 dollars per comic

500

Find the constant of proportionality with correct units

60 miles per hour

500

An item that is 4 feet long is 48 inches long.   What is the unit rate per foot?

 12 in per foot

500

In a laboratory, scientists performed chemical reactions.  The amount of product formed by a reaction can be determined by P = 0.25r, where P is the product and r is the amount of reactants used.  Find k with correct units.

k = 0.25 product per reactant

500

Sprinters—Usain Bolt is the fastest sprinter in the world. Marcos thinks he can outrun him. Usain bolt can run 36 miles in 2 hours. Xavier can run 6 miles in 0.5 hours. Who is the fastest runner? Explain how you know.

Usain bolt is faster because he runs at a rate of 18 miles per hour, but Xavier can only run 12 miles per hour