SOLUTION: John takes three times longer than Andrew to peel 400 pounds of apples. Working together they can peel 400 pounds of apples in 8 hours. How long would it take John to peel them alo

Algebra ->  Rate-of-work-word-problems -> SOLUTION: John takes three times longer than Andrew to peel 400 pounds of apples. Working together they can peel 400 pounds of apples in 8 hours. How long would it take John to peel them alo      Log On


   



Question 161429: John takes three times longer than Andrew to peel 400 pounds of apples. Working together they can peel 400 pounds of apples in 8 hours. How long would it take John to peel them alone?
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
x*3x/(x+3x)=8
3x^2=8*4x
3x^2=32x
3x^2-32x=0
x(3x-32)=0
3x-32=0
3x=32
x=32/3 or 10.667 Andrew's time.
3x=3*10.66=32 John's time.
Proof:
10.667*32/(10.667+32)=8
341.333/42.667=8
8=8