SOLUTION: Dan can shovel dirt off his lawn in 40min. He shovels for 20 min and then is joined by Tom. If they shovel the remaining dirt in 10min, how long would it have taken Tom to shovel
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-> SOLUTION: Dan can shovel dirt off his lawn in 40min. He shovels for 20 min and then is joined by Tom. If they shovel the remaining dirt in 10min, how long would it have taken Tom to shovel
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Question 101333: Dan can shovel dirt off his lawn in 40min. He shovels for 20 min and then is joined by Tom. If they shovel the remaining dirt in 10min, how long would it have taken Tom to shovel the lawn alone? Please help. Thanks Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! Dan can shovel dirt off his lawn in 40 min. He shovels for 20 min and then is joined by Tom. If they shovel the remaining dirt in 10min, how long would it have taken Tom to shovel the lawn alone?
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Let x = time required if Tom does it alone
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Let the completed job = 1
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Total worked by Dan is 20 min + 10 min = 30 min
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Dan's work + Toms work = completed job
: + = 1
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multiply equation by 40x to get rid of the denominator:
40x* + 40x* = 40x(1)
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CAncel the denominator and you have:
30x + 40(10) = 40x
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30x + 400 = 40x
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400 = 40x - 30x
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400 = 10x
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x = 400/10
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x = 40 minutes for Tom working by himself (Same as Dan)
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Check it: + = 1
