Question

A swimmer swam 1000 meters downstream in 15 minutes and swam back in 30 minutes against the current. what was the rate of the swimmer in still water? how fast was the current?

Answer 1

1000 = (v+c)15 = 15 v + 15 c
1000 = (v-c)30 = 30 v - 30 c
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2000 = 30 v + 30 c
1000 = 30 v - 30 c
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1000 = 60 c etc