SOLUTION: Jim and his dad are bricklayers. Jim can lay bricks for a fireplace and chimney in 5 days. With his father's help he can build it in 2 days. How long would it take his father to bu

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Question 996069: Jim and his dad are bricklayers. Jim can lay bricks for a fireplace and chimney in 5 days. With his father's help he can build it in 2 days. How long would it take his father to build it alone?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Jim and his dad are bricklayers. Jim can lay bricks for a fireplace and chimney in 5 days.
With his father's help he can build it in 2 days.
How long would it take his father to build it alone?
:
let d = time required by Dad working alone
let the completed job = 1
:
A typical "shared work" equation
2%2F5 + 2%2Fd = 1
multiply equation by 5d
5d*2%2F5 + 5d*2%2Fd = 5d*1
Cancel the denominators and we have
2d + 5(2) = 5d
10 = 5d - 2d
10 = 3d
d = 10/3
d = 31%2F3 days, Dad alone