Swati can row her boat at a speed of 5km/hr in still water. if it takes her 1 hour more to row the boat 5.25 km upstream than to return downstream, Find the speed of the stream.

Explanation

Let speed of stream is `v` km/h.

So, speed at downstream will be `5+v` km/h and speed at upstream will be `5-v` km/h.

As, difference in time taken by the boat to row is `1` hour,

`:. 5.25/(5-v) -5.25/(5+v) = 1`

`=>5.25(5+v+-5+v) = 25-v^2`

`=>v^2 +11.5v -25 = 0`

`=>v = (-11.5 +- sqrt(132.25+100))/2`

`=>v = (-11.5+15.23)/2 = 1.86`km/h

...