SSC Sample Paper Mock Test-11 SSC CGL Tear-II Paper-1

The speed of a motorboat is that of the stream of water as 36: 5. The boat goes along with the stream in 5 h 10 min. It will come back in

A) 5 h 50 min

B) 6 h

C) 6 h 50 min

D) 12 h 10 min

Correct Answer: C

Solution :

Let the speed of motorboat = 36x km/h

and speed of stream = 5x km/h

The boat goes along with the current in 5 h 10 min i.e., \[\frac{31}{6}\text{h}\text{.}\]

\[\therefore \] Distance \[=\frac{31}{6}\times (36+5x)\]

\[=\frac{41x\times 31}{6}\text{km}\]

Rate upstream \[=36x-5x=31\,\,x\,\,\text{km/h}\]

\[\therefore \] Time taken \[=\frac{41x\times \frac{31}{6}}{31x}=\frac{41}{6}\]h = 6 h 50 min