Question

Ray is purchasing a laptop that is on sale for 25% off. He knows the function that represents the sale price of his laptop is c(p) = 0. 75p, where p is the original price of the laptop. He also knows he has to pay 8% sales tax on the laptop. The price of the laptop with tax is f(c) = 1. 08c, where c is the sale price of the laptop. Determine the composite function that can be used to calculate the final price of ray's laptop.

Answer 1

the final price of Ray's laptop is 89.1% of the original price.

Explanation:

To find the composite function that can be used to calculate the final price of Ray's laptop, we need to find the composition of the two functions given:

f(c) = 1.08c (function for calculating the price of the laptop with tax)

c(p) = 0.75p (function for calculating the sale price of the laptop)

We can find the composite function f(c(p)) by substituting c(p) into the formula for f(c):

f(c(p)) = 1.08c(p)

Substituting c(p) with 0.75p, we get:

f(c(p)) = 1.08(0.75p)

Simplifying, we get:

f(c(p)) = 0.81p

Therefore, the composite function that can be used to calculate the final price of Ray's laptop is f(c(p)) = 0.81p.

This means that to find the final price of the laptop, we need to take the original price, multiply it by 0.75 to get the sale price, and then multiply the sale price by 1.08 to add the sales tax. In other words, the final price is:

final price = f(c(p)) = 0.81p = 1.08(0.75p)

final price = 0.81p + 0.081p

final price = 0.891p

Therefore, the final price of Ray's laptop is 89.1% of the original price.