SOLUTION: twin brothers, Billy and Bobby, can mow their grandparents lawn together in 114 minutes. Billy could mow the lawn by himself 45 minutes less time that it would take Bobby. How long

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Question 766906: twin brothers, Billy and Bobby, can mow their grandparents lawn together in 114 minutes. Billy could mow the lawn by himself 45 minutes less time that it would take Bobby. How long would it take Bobby to mow the lawn by himself?
Answer by josgarithmetic(39616) About Me  (Show Source):
You can put this solution on YOUR website!
L BiLLy's rate
B Bobby's rate
Their combined rate 1/L+1/B=1/114 lawns per minute
Let m = minutes for Bobby to do the job himself.
Bobbys rate, 1%2FB=1%2Fm.
Billy's rate 1%2FL=1%2F%28m-45%29.

Revise the rate information:
Billy's rate, 1%2F%28m-45%29 lawns per minute
Bobby's rate, 1%2Fm lawns per minute.

Their combined rate is given, so highlight%281%2F%28m-45%29%2B1%2Fm=1%2F114%29
One variable, m, so solve for m.

Simplifies to m%5E2-27m%2B570=0
Solution to quadratic equation gives m=148 minutes.
Bobby's rate is one lawn mowed in 148 minutes.