Question

Exit Ticket

A plumber charges a one-time surcharge fee of $50 for
emergency calls plus a rate of $65 per hour. Write a function
using function notation to determine the total amount charged
for an emergency service call. Then find f(4.5), and explain the
real-world interpretation of f(4.5).

Answer 1

f(x) = $65x + $50

f(4.5) = $342.5

The real-world interpretation of f(4.5) would be an emergency service call where they have to work for 4.5 hours.

Explanation:

We will write a function where x is the hours. Since you pay $65 for every hour, we will multiply $65 by x. Next, there is a fee of $50 so we will add that onto the end.

f(x) = $65x + $50

Now, we will plug 4.5 into the function for x and solve.

f(x) = $65x + $50

f(4.5) = $65(4.5) + $50

f(4.5) = $292.5 + $50

f(4.5) = $342.5

The real-world interpretation of f(4.5) would be an emergency service call where they have to work for 4.5 hours.