Question 414612
John paddled for 4hrs with a 4 km/hr current to reach a campsite. The return trip against the same current took 10hrs. Find the speed of John's canoe in still water. 
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With Current DATA:
time = 4 hrs ; rate = c+4 km/h ; distance = t*r = 4(c+4) = 4c+16 km
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Against Current DATA:
time = 10 hrs ; rate = c-4 km/h ; distance = t*r = 10(c-4) = 10c-40 km
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Equation:
distance with = distance against
4c+16 = 10c-40
6c = 56
c = 9 1/3 km/h (speed of the canoe in still water)
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Cheers,
Stan H.
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