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.