SOLUTION: If man rows a boat 500feet upstream against constant current in 10min,while return trip cover 300feet in 5 mins, find speed of current and and equivalent rate at which he can row i

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Question 1050644: If man rows a boat 500feet upstream against constant current in 10min,while return trip cover 300feet in 5 mins, find speed of current and and equivalent rate at which he can row in still water?
Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
let r be the rate of the man's rowing and c be the rate of the current, then
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1) (r-c) * 10 = 500
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2) (r+c) * 5 = 300
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solve equation 1 for c
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10r -10c = 500
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c = (10r - 500) / 10 = r - 50
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substitute for c in equation 2
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(r + r - 50) * 5 = 300
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10r - 250 = 300
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10r = 550
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r = 55 feet per minute
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c = 55 - 50 = 5 feet per minute
:
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man rows at 55 feet per minute
current is 5 feet per minute
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