App Logo

No.1 PSC Learning App

1M+ Downloads
A boat starting from point P goes downstream to point Q in 3 hours and returns back from point Q to the point P in 4 hours. If the speed of the water is 3 km/h, find the speed of the boat in still water.

A20 km/h

B12 km/h

C32km/h

D21 km/h

Answer:

D. 21 km/h

Read Explanation:

speed in still water = V

speed of water =3

speed in downstream =V+3

speed in upstream =V-3

time taken downstream = 3hrs

time taken upstream = 4hrs

d=(v+3)×3d=(v+3)\times3

d=(v3)×4d=(v-3)\times4

(v+3)×3=(v3)×4)(v+3)\times 3=(v-3)\times 4)

3v+9=4v123v+9=4v-12

v=21v=21


Related Questions:

A boatman goes 4 km against the current of the stream in 1 hour and goes 2 km along the current in 10 minutes. How long will it take to go 24 km in stationary water?
A man rows to a place 35 km in distant and back in 10 hours 30 minutes. He found that he could row 5 km with the stream in the same time as he can row 4 km against the stream. Find the rate of flow of the stream.:
A boy can swim in still water at a speed of 10 km/hr. If the speed of the current would have been 5 kmph, then the boy could swim 60km
The speed of a boat in still water is 20 kmph, and the speed of the stream is 2 kmph. In how many hours would the boat cover a distance of 198 km downstream?
If sum of upstream and downstream speed of a boat is 82 kmph, and the boat travels 105 km. upstream in 3 hr, Find the time taken by boat to cover 141 km downstream.