A motor boat whose speed is 18 km/h m still water takes 1 hour more to go 24 km upstream than to return downstream to the same spot. Find the speed of the stream.

Explanation

let speed of stream = `x`

time taken to go upstream `= 24/(18-x)`

time taken to return downstream = `24/(18+x)`

according to question

`24/(18-x) = 24/(18+x) + 1`

`24/(18-x) - 24/(18+x) = 1`

`24[1/(18-x) - 1/(18+x)] = 1`

`24[(18+x -(18-x))/((18-x)(18+x))] = 1`

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