The speed of a swimmer in still water is 8 km/hr and the speed of stream is 2 km/hr. The swimmer takes 6 hours more to cover a distance upstream than to cover a distance downstream. Find the distance.

90 km

ATQ,     (D.S) Downstream speed = 8 + 2 = 10 km/hr

            (U.S) Upstream speed = 8 - 2 = 6 km/hr

             Distance = \(\frac{D.S × U.S}{D.S - U.S}\) × Time

                          = \(\frac{10 × 6}{10 - 6}\) × 6 = \(\frac{60}{4}\) × 6 = 90 km