7th Grade Math

Test PracticeT

C 13. FIND THE ERROR Blake ran laps around the gym. His times are shown

in the table. Blake is trying to decide whether the number of laps is

proportional to the time. Find his mistake and correct it.

It is proportional

because the number of

laps always increases

by 2.

Time (min) 1234

Laps 46810

CHALLENGE For each of the following, determine whether each situation

is sometimes, always, or never proportional. Explain your reasoning.

14. the cost for ordering multiple items that will be delivered


15. the number of cars on a highway and the number of tires


16. E WRITE MATH Explain what makes two quantities proportional.


17. Mr. Martinez is comparing the price of
    oranges from several different markets.
    Which market’s pricing guide is based
    on a constant unit price?

A. (^) Number of Oranges 5 101520
Total Cost ($) 3.50 6.00 8.50 11.00
B. (^) Number of Oranges 5 101520
Total Cost ($) 3.50 6.50 9.50 12.50
C. (^) Number of Oranges 5 101520
Total Cost ($) 3.00 5.00 7.00 9.00
D. (^) Number of Oranges 5 101520
Total Cost ($) 3.00 6.00 9.00 12.00

18. GRIDDED RESPONSE The middle
    school is planning a family movie night
    where popcorn will be served. The
    constant relationship between the
    number of people n and p, the number
    of cups of popcorn, is shown in the
    table. How many people can be served
    with 519 cups of popcorn?

n 30 60 120?

p 90 180 360 519

19. Which relationship has a unit rate of
    60 miles per hour?
    F. 300 miles in 6 hours
    G. 300 miles in 5 hours
    H. 240 miles in 6 hours
    I. 240 miles in 5 hours

Lesson 1C Proportions 275

265_281_C05_L1_895130.indd 275 12/29/09 12:58 PM