Question

Bill's Plumbing Service charges $75 to schedule a repair visit plus $30 per hour to make repairs. If the total bill was $177, how many hours did Bill work on the repair?

Answer 1

Let \( x \) be the number of hours Bill worked on the repair. The total cost can be expressed as:

\[
\text{Total cost} = \text{Scheduling fee} + \text{Hourly charge} \times \text{Number of hours}
\]

Substituting the known values:

\[
177 = 75 + 30x
\]

To isolate \( x \), first subtract the scheduling fee from both sides:

\[
177 - 75 = 30x
\]

This simplifies to:

\[
102 = 30x
\]

Next, divide both sides by 30 to solve for \( x \):

\[
x = \frac{102}{30}
\]

Calculating the right side gives:

\[
x = 3.4
\]

Therefore, Bill worked for \( 3.4 \) hours on the repair.