Question

Jack works after school. Each day he earns a set amount, plus an hourly wage.

Hours 1 1.5 2 2.5 3
Pay 18 23 28 33 38

Part A

Write a linear function f Jack can use to determine his pay.
A. f(x) = 10x + 8
B. f(x) = 15x + 3
C. f(x) = 0.5x + 1
D. f(x) = x + 18
Part B

Which is a reasonable domain?
A. 0 < x < 6
B. 0 < x < 24
C. 0 < x < 68
D. 0 < x < 248
Part C

Assume Jack works from 2:30 P.M. to 7:00 P.M. How much would he earn?
A. $33
B. $35.50
C. $45
D. $53

Answer 1

Part A: A. f(x) = 10x + 8
- Pay increases by $5 for each 0.5 hour → $10 per hour. Using (1,18): 10(1)+b=18 → b=8.

Part B: A. 0 < x < 6
- Domain should be positive and realistically limited (after school, a few hours), so under 6 hours is reasonable.

Part C: D. $53
- From 2:30 to 7:00 is 4.5 hours. f(4.5)=10(4.5)+8=45+8=53.