Question

Pedro works as a newspaper deliverer. He receives a base pay plus an additional amount per newspaper delivered. Last week, Pedro delivered 5 newspapers and earned $37.50. This week, he delivered 20 newspapers and earned $75. Let x equal the number of newspapers Pedro delivers and y be the earnings he receives in dollars. Which linear function models the scenario?

Answer 1

y = base pay + (variable pay * x)

37.50 = base pay + (variable pay * 5)
75 = base pay + (variable pay * 20)

let v be the variable pay: 
base pay = y - variable pay * x
37.50 - 5v = 75 - 20v
-5v + 20v = 75 - 37.50
15v = 37.50
v = 37.50/15
v = 2.5

37.50 - 5(2.5) = 75 - 20(2.5)
37.50 - 12.50 = 75 - 50
25 = 25

base pay is 25 ; variable pay is 2.50 per newspaper delivered.

y = 25 + 2.50x