Question

A delivery service charges a base price for an overnight delivery of a package plus an extra charge for each pound the package weighs. A customer is billed $22.85 for shipping a 3-pound package and $40 for shipping a 10-pound package.

Answer 1

Write an equation that gives the total cost of shipping a package as a function of the weight of the package.

Answer 2

Let C be the total charge
B= base price
x= weight in punds
charge per pound =P
C=B+Px
for 3 pounds
C=22.85
a) 22.85=B+3P
for 10 pounds C=40
b) 40=B+10P
subtracting a from b
17.15=7P
P=2.45 per pound
40=B+24.5
B=15.5
so total
Charge =15.5+2.45x
x=weight in pounds

Answer 3

Find the cost of shipping a 15-pound package.

Answer 4

put x=15 pound in charge equation
charge=15.5+2.45*15=
you find now

Answer 5

$52.25