Discussion of Question with ID = 082 under Boats-and-Streams

This is the discussion forum for this question. If you find any mistakes in the solution, or if you have a better solution, then this is the right place to discuss. A healthy discussion helps all of us, so you are requested to be polite and soft, even if you disagree with the views of others. The question and its current solution has also been given on this page.



A boat can travel 300 km downstream in 30 hours. If it covers the same distance upstream in 50 hours, what is the speed of the boat in still water?


8 kmph.


9 kmph.


7 kmph.


11 kmph.

Ans: a

The downstream speed = $300/30$ = 10 km/h, and the upstream speed = $300/50$ = 6 km/h. By the shortcut method, the speed of the boat in still water is average of the downstream and upstream speeds of the boat. So the required speed = ${10 + 6}/2$ = 8 km/h.

Comments and Discussion