Direct Variation Review

A person’s weekly pay is directly proportional to the number of hours worked. Shawn’s pay is $123.00 for 20 hours of work. Find the amount of pay for 31 hours of work. 

• $3813

• $620

• $190.65

• $4.96

What is the constant of proportionality (in miles per hour) based on the table?

• 45

• 90

• 135

• 2

y varies directly as x ,If y = 8, when x = 4, find y when x = 48.

• 88

• 24

• 48

• 96

y varies directly as x ,If y = 9, when x = -3, find x when y = -27.

• 9

• -9

• 27

• -27

y varies directly as x ,If y = 22, when x = -11, find x when y = 88.

• -22

• 22

• -44

• 44

The gas pressure in a chamber varies directly with the temperature in the chamber. If the pressure in the chamber is 150 atmospheres (atm) when the chamber is at 50 degrees, what is the pressure in the chamber when the temperature of the chamber is 75 degrees? 

• 175 atm

• 200 atm

• 225 atm

• 275 atm

The number of words Maria typed varied directly with the amount of time she spent typing. If she typed 275 words in 5 minutes, how long would it take her to type 1,100 words?

• 220 minutes

• 20 minutes

• 15 minutes

• 4 minutes 

The amount of money earned on a job is directly proportional to the number of hours worked.  If $70.00 is earned in 5 hours, how much money is earned in 22 hours of work?

• $2

• $308

• $1.57

• $265

The number of soft pretzels processed by a machine in a bakery is directly proportional to the
number of minutes that the machine runs. The machine can process 600 pretzels in 10 minutes of
continuous running. How many pretzels would the machine process in 52 minutes of continuous
running?

• 1,200

• 1,500

• 3,120

• 5,200

Emily is selling greeting cards. The graph models the linear relationship between the number of boxes of cards she sells and her profit. Which of these bests describes the profit Emily makes from selling cards?

• $7.50 per box

• $10.00 per box

• $4.00 per box

• $3.00 per box