CSC Company Numerical Ability Boats and Streams

Two boats A and B of engine speed u travel in opposite directions in a stream of speed a. Let A travel in the direction of stream. Let the distance between them be s. What time they will cross each other.

a. s/(2u) b. (2s)/u c. can't be determined d. s/u

Read Solution (Total 1)

speed of boat A upstream = u - a
speed of boat B downstream = u + a
Relative speed of A with respect to B = u - a + u + a = 2u
Time taken for boats to cross each other = distance between them / relative speed = s/2u
12 years agoHelpfull: Yes(0) No(0)

CSC Other Question

A boat with still water speed of a is traveling upstream where the streams speed is b. After covering certain distance s, the boat turns back and tries to come to the starting place. But the boat stops at 3/4th of the intended distance due to a technical fault. What is the ratio of the time taken for the return journey to that of the upstream journey.

a. 3(a - b)/4(a + b) b. 4(a - b)/3(a + b) c. 3(a + b)/4(a - b) d. 4/3 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%