CSC Company Numerical Ability Boats and Streams

Let a boat traveling in still water with a speed of 30 kmph covers a certain distance in 9 hours. Now if the same distance has to be covered traveling upstream in a speed of 10 Kmph, by what percentage the speed of the boat should be increased to cover the distance in the same time of 9 hours.

a. 33.33% b. 66.66% c. 24.47% d. 60%

Read Solution (Total 1)

Speed of boat in still water = 30 Kmph.

Speed of boat in upstream would be 30 - 10 = 20 Kmph

To balance for the reduction in speed caused by the upstream, the engine speed has to be increased by 10kmph so that the effective speed becomes 30 kmph again.

Therefore, percentage increase in speed = increase in speed / original speed X 100% = 10/30 X 100% = 33.33%.
11 years agoHelpfull: Yes(0) No(0)

CSC Other Question

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