Question

It takes Bill 8 hours to paint a house. It take Paul 4 hours to paint a house. And it takes Quincy 9 hours to paint a house. How many hours would it take them working together?

Answer 1

2 2/35 hours

Explanation:

In 1 hour, the total amount of the house that is painted is ...

1/8 + 1/4 + 1/9 = 35/72 . . . of a house

We need to multiply the time (1 hour) by 72/35 to find the number of hours required for one entire house:

72/35(1 h) = 2 2/35 h

It would take them 2 2/35 hours to paint the house working together.