. Carpenter Charlie charges $15 per hour plus a flat rate of $100. Carpenter Chris charges $20 per hour plus a flat rate of $50. For how many hours of work will the total charged be equal? Let x = the number of hours worked and let y = the total that the carpenter will charge. I'm not sure how to write it out

The indifference point is 10 hours.

Step-by-step explanation:

Giving the following information:

Carpenter Charlie charges $15 per hour plus a flat rate of $100. Carpenter Chris charges $20 per hour plus a flat rate of $50.

First, we need to structure the total cost formula for each option:

Charlie:

y= 100 + 15x

Chris:

y= 50 + 20x

Now, we equal both formulas and isolate x:

100 + 15x = 50 + 20x

50= 5x

10=x

The indifference point is 10 hours.

Prove:

y= 100 + 15*10= $250

y= 50 + 20*10= $250