Question

A plumber charges $17 to visit a client's home, plus an additional $36 per hour. What is the

duration, in hours, of a plumber's visit that costs $89?

Answer 1

Because this is a linear problem, I'd use the slope-intercept formula:

`y = mx + b`

where

m = slope (rise/run)

y = dependent value

x = independent value

b = constant value

Because the plumber charges $17 upon arrival, it is our constant. The $36 is our slope (per hour, per minute, per etc. is generally a give away). Additionally because the total cost of the plumber's visit depends on how long s/he stays at a client's home, the $89 is our y value. Therefore the equation should look like this:

`89 = 36x + 17`

Solve for x by subtracting 17 from both sides of the equation then dividing by 36.

`72 = 36x`

`2 = x`

The plumber spent two hours at his/her client's home.

Answer 2

I believe the duration for $89.00 is 2 hours

Explanation:

We start off with the $17 dollars and calculate 36.00+36.00 for a total of $89. Therefore, (120 mins)/60=2 hours.