SOLUTION: When all the leaves have fallen, a girl can rake the entire yard in 8 hours. When a boy does it alone, it takes him 9 hours. How long would it take them to rake the yard together.

Algebra ->  Rate-of-work-word-problems -> SOLUTION: When all the leaves have fallen, a girl can rake the entire yard in 8 hours. When a boy does it alone, it takes him 9 hours. How long would it take them to rake the yard together.      Log On


   

Question 901751: When all the leaves have fallen, a girl can rake the entire yard in 8 hours. When a boy does it alone, it takes him 9 hours. How long would it take them to rake the yard together.
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
1%2F8+%2B+1%2F9+=+1%2Fx
9x + 8x = 72
17x = 72
x = 72/17 hr 0r 4 4/17 hr