7th Grade Math

Test PracticeT

382 Linear Functions

24. The table shows the number of hand
    painted T-shirts Mi-Ling can make after
    a given number of days.

Number of

Days, x

Total Number

of T-Shirts, y

16

212

318

424

Which function rule represents

the data?

A. y = 4 x

B. y = 5 x

C. y = 6 x

D. y = 12 x

25. Rosa needs to have 50 posters printed to
    advertise a community book fair. The
    printing company charges $3 to print
    each poster. Which table represents this
    situation?

F. (^) Posters Cost ($)
33
66
99
pp
H. (^) Posters Cost ($)
13
26
39
p 3 + p
G. (^) Posters Cost ($)
13
26
39
p 3 p
I. (^) Posters Cost ($)
31
62
93
pp ÷ 3

19. FIND THE ERROR Divya is finding the range for the
    function y = 3 x given the domain {2, 4, 6, 8}.
    Find her mistake and correct it.

C

20. OPEN ENDED Write about a real-world situation that could be
    represented by the function 12n.


21. CHALLENGE A function is shown in the table below.

x 2468

y 0.5 1.0 1.5 2

a. Write a function rule for the function.

b. Use the rule from part a. Find the value of y, if x = 10, 12, and 14.

22. CHALLENGE Write a rule for the function represented by {(1, 2), (2, 5),
    (3, 10), (4, 16)}.


23. E WRITE MATH Explain the relationship among an input, an output,
    and a function rule.

If y = 3x and I have the inputs of

2, 4, 6, and 8, then the outputs

should be 5, 7, 9, and 11.

377_384_C07_L1_895130.indd 382 12/31/09 4:23 PM