Constant of Proportionality In Words
Constant of Proportionality Equations
Tables and Graphs
Unit Rate/Better Buy
100
Jude sends 45 E-mails in 15 minutes.
How many E-mails did he send per minute?
He sent 3 E-mails per minute.
100
Jessica earns $12 per hour. Write an equation that represents Jessica's earnings.
y = 12x
100
Does this table show a proportional relationship?Explain.
Yes, it is proportional because the unit rates are all $1.50 per ticket.
100
What is the unit price for 6 pounds of turkey for $18.69
$3.12 per pound
200
Lena earned $640 in a 40-hour work week.
What is Lena's hourly rate of pay?
Lena earns $16 per hour.
200
Gianna reads 27 pages in 9 minutes. At What rate does Gianna read?
Write an equation for this relationship.
Gianna reads 3 pages per minute.
y = 3x
200
Does this table show a proportional relationship? Explain. 
No, it is not proportional because the unit rates are not the same.
200
What is the unit price for 4 1/4 pounds of peanuts for $5.78?
$1.36 per pound.
300
A helicopter propeller spins 2400 revolutions in 4 minutes. What is the constant of proportionality (k), in revolutions per minute?
The constant of proportionality is k = 600 RPM.
300
Maxine works at law office. the equation y = 135x. Let y represent her earnings and x represent her hours worked. Determine how much money she makes if she works 40 hours.
Maxine earns $5,400 in 40 hours.
300
A graph represents a proportional relationship if:
1.
2.
1. It is a straight line
2. It passes through the origin
300
Gasoline is $4.20 per gallon. How much will it cost Henrico to purchase 25 gallons?
$105
400
Jeff earned $400 working a 40-hour work week.
Find Jeff's hourly wage and use it to predict how much he will make if he works for 47 hours.
Jeff makes $10 per hour and would make $470 IN 47 hours.
400
The equation y = 55x represents the rate of the Long Island highway speed limit, in miles per hour. Let x represent the number of hours driven and y represent the total miles driven.
How long was Francis driving if he drove 247. 5 miles at the speed limit.
Francis drove for 4.5 hours.
400
Does this graph show a proportional relationship? Explain
No, it is not proportional because it does not touch (0, 0)
400
At a candy store, 3 giant lollipops sell for $7.59 and 2 small packets of bubblegum cost $4.82. Which is a better buy?
The 2 small packets of bubblegum.
500
Janine sells 16 apples for $8.00. What is the unit price for each apple?
How much would she earn if she sold 64 apples?
The unit price is $0.50 per apple.
Janine would earn $32 for selling 64 apples.
500
If Jackson ate hamburgers at a rate of 3.5 hamburgers per minute and Jacen ate hamburgers at a rate of 4.7 hamburgers per minute, how many more hamburgers Jacen can eat more than Jackson? Use this number to write an equation.
y = 1.2x
500
What is the constant of proportionality of this graph?
k = 1/6
500
At a toy store you can get 2 board games for $18.36. Online the price for 3 board games is $27.56. Which place has the highest price for a board game? Show your work to explain.
Online is highest because it costs $9.19 per game.