Question 785852
A man swims  downstream from the shore to a certain point at an effective rate of 10 ft/min. He swims back from this point to the shore at an effective rate of 4 ft/min. If it took him 14 min altogether, how far out from the shore did he go?
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Avg speed for the round trip =
2*10*4/(10+4) = 40/7 ft/min
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d = r*t = (40/7)*14 = 80 feet
--> 40 feet each way