Question 205859
James can row 14 km downstream in a river in 2 hours. He takes 7 hours to go back. Find the speed of the current and the speed of James in still water.
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d = rt
c = speed of current, r = rowing speed
14 = (r+c)*2 = (r-c)*7
2r+2c=14
7r-7c=14
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r+c=7 Eqn 1 div by 2
r-c=2 Eqn 2 div by 7
----- Add equations
2r = 9
r = 4.5 kph
c = 2.5 kph