A man goes upstream for 10 km in 5 hour .another man goes downstream for 10 km in 3 hour .if speed of stream is 15 km/h what is the difference in speed of both men.

Since, speed in upstream is
                     10/5 = 2 kmph 
and the speed in downstream is
                      10/3 kmph
Then, the upstream is
                      15-2 = 13 kmph 
and downstream is
                      15+10/3 = 18.33 kmph
Hence,  the difference is 18.33-13.00= 5.33