College

An HVAC technician charges a [tex]\$150[/tex] flat fee to inspect an air conditioning system that is malfunctioning. If the customer chooses to make the repair, the technician charges an additional [tex]\$75[/tex] per hour for every hour of labor needed to complete the repair. Which of the following equations describes the cost of a repair ([tex]C[/tex]), in terms of how many hours ([tex]t[/tex]) the technician works?

A. [tex]C = 75 + 150t[/tex]
B. [tex]C = 75t + 150[/tex]
C. [tex]150C + t = 75[/tex]
D. [tex]C + 75t = 150[/tex]

Answer :

Let's examine the problem step by step.

1. Flat Fee: The HVAC technician charges a flat fee of [tex]$150 just for inspecting the air conditioning system. This is a one-time charge that applies regardless of the number of hours worked.

2. Hourly Rate for Repairs: If the customer decides to proceed with the repair, the technician charges an additional $[/tex]75 for each hour of labor. This means for every hour the technician works, the total cost increases by [tex]$75.

3. Total Cost Calculation: To determine the total cost \( C \) of the repair, we need to consider both the flat fee and the hourly rate. Let \( t \) represent the number of hours the technician works on the repair.

4. Equation Setup:
- The flat fee is $[/tex]150.
- The hourly cost for \`t\` hours of repair work is $75 times [tex]\( t \)[/tex], or [tex]\( 75t \)[/tex].

Thus, the total cost [tex]\( C \)[/tex] is the sum of the flat fee and the hourly charges. Therefore, the equation that describes the total cost [tex]\( C \)[/tex] in terms of the number of hours [tex]\( t \)[/tex] is:

[tex]\[ C = 75t + 150 \][/tex]

This means the correct equation is [tex]\( C = 75t + 150 \)[/tex].