Direct Variation Problems

Heather’s weekly pay varies directly with the number of hours that she works at the record store. Heather is paid $174 for 24 hours of work. Find the amount of pay for 40 hours of work.

Hint: Set up a proportion

• $960

• $250

• $300

• $290

Eduardo counted 10 seconds between seeing lightning and hearing thunder, and he knew that the lightning was about 2 miles away. If he counted 4 seconds between the next flash and the thunder, about how far away was the lightning?

Hint: Set up a proportion.

• 1.5 miles

• 0.8 miles

• 5 miles

• 20 miles

A person’s weekly pay varies directly to the number of hours worked. Shawn’s pay is $123.00 for 20 hours of work. What would Shawn’s pay be if he worked for 31 hours?

Hint: Set up a proportion

• $180.50

• $620.00

• $190.65

• $210.75

The distance a rabbit can run varies directly to the amount of minutes the rabbit runs. At top speed, a rabbit can cover 7 miles in 12 minutes. If a rabbit could continue at this pace, how long will it take the rabbit to cross the 220-mile expanse of the Mojave Desert?

Hint: Set up a proportion; round if needed.

• 377.14 minutes

• 400 minutes

• 84 minutes

• 2.62 minutes

The amount of water a dishwasher uses varies directly with the number of loads of dishes it washes. If a dishwasher uses 65 gallons of water to wash 5 loads of dishes, it uses (a)   gallons of water to wash 12 loads of dishes.

Tags

TEKS.MATH.7.4C

TEKS.MATH.7.4A

y varies directly as x. If x = 5 when y = 12, find x when y = 30.

Hint: Set up a proportion.

• 15

• 10

• 12.5

• 20

y varies directly as x. If x = 4 when y = 12, what is the value of y when x = 7? The value of y is (a)  

y varies directly as x. If y = 80 when x = 8, what is the value of y when x = 12? The value of y is (a)   .

Hint: Set up a proportion.

y varies directly as x. If y = 75 when x = 25, find x when y = 25.

Hint: Set up a proportion; round if needed.

• 5

• 8

• 75

• 25

y varies directly as x. If y = 15 when x = -18, find y when x = 1.6.

Hint: Set up a proportion; round if needed.

• 1.33

• 1.6

• -1.33

• -168.75