Question

Challege anyone?

A plumber and his assistant work together to replace the pipes in an old house. The plumber charges $40 an hour for his own labor and $15 an hour for his assistant's labor. The plumber works twice as long as his assistant on this job, and the labor charge on the final bill is $3325. How long did the plumber and his assistant work on this job?

Answer 1

plumber's charge = $40 an hour
assistant's charge = $15 an hour

plumber's time working = 2 * that of his assistant

Total charge: plumber's charge an hour * amount of hours worked + assistant's charge an hour * amount of hours worked

Total charge: 40 * (2a) + 15 * a = 3325
80a + 15 a = 3325
95 a = 3325
19 a = 665
a = 665/19 = 35

Answer 2

HOw much for plumbler then his assistant?

Answer 3

a is the amount of time the assistant worked, hence the 2a as the time the plumber worked. So a = 35 = time assistant worked, time plumber worked = 70.

Answer 4

Thanks!

Answer 5

You're welcome!