Problema Solution

The cost y

(in dollars) to rent a pickup truck is proportional to the number x

of hours that the pickup truck is rented. It costs $100 to rent the truck for 4 hours. Write an equation that represents the cost to rent a pickup truck for x

hours.

Answer provided by our tutors

Since y is proportional to x we have:

y =  kx, where k is constant

For x = 4 hr we have y = $100 that is:

100 = 4k

4k = 100 divide both sides by 4

k = 100/4

k = 25

The equation that represents the cost to rent a pickup truck for x hours is:

y = 25x