Topics

General Knowledge
General Science
General English
Aptitude
General Computer Science
General Intellingence and Reasoning
Current Affairs
Exams
Elementary Mathematics
English Literature

Keshav can row 60 km downstream and 36 km upstream, taking 10 h each time. What is the velocity of the current?

A) 3 km/h
B) 2.2 km/h
C) 4 km/h
D) 1.2 km/h

Correct Answer:




D) 1.2 km/h

Description for Correct answer:
Speed downstream = \( \Large \frac{Distance}{Time} = \frac{60}{10} \) = 6 km/h

Speed upstream = \( \Large \frac{Distance}{Time} = \frac{36}{10} \) = 3.6 km/h

Therefore, Velocity of the current

= \( \Large \frac{1}{2} \) (Speed downstream - Speed upstream)

= \( \Large \frac{1}{2} \left(6-3.6\right) = \frac{2.4}{2} \) = 1.2 km/h

Part of solved Boat and Stream questions and answers : >> Aptitude >> Boat and Stream

Comments

Similar Questions

1). What time will be taken by a boat to cover a distance of 128 km along the stream, if speed of a boat in still water is 24 km/h and speed of stream is 8 km/h?

A). 8 hrs

B). 4 hrs

C). 7 hrs

D). 6 hrs

2). A motorboat can travel at 10 km/h in still water. It travelled 91km downstream in a river and then returned to the same place, taking altogether 20 h. The rate of flow of river is

A). 3 km/h

B). 4 km/h

C). 2 km/h

D). 5 km/h

3). A man can row against the current three-fourth of a kilometre in 15 min and returns same distance in 10 min, then ratio of his speed to that of current is

A). 3 : 5

B). 5 : 3

C). 1 : 5

D). 5 : 1

4). The speed of the current is 5 km/h. A motorboat goes 10 km upstream and back again to the starting point in 50 min. The speed, (in km/h) of the motorboat in still water is

A). 20 km/h

B). 26 km/h

C). 25 km/h

D). 28 km/h

5). A man can row 6 km/h in still water. If the speed of the current is 2 km/h, it takes 3 h more in upstream than in the downstream for the same distance. The distance is

A). 30 km

B). 24 km

C). 20 km

D). 32km

6). A boat goes 48 km downstream in 20 h. It takes 4 h more to cover the same distance against the stream. What is the speed of the boat in still water?

A). 2.2 km/h

B). 2 km/h

C). 4 km/h

D). 4.2 km/h

7). Pawan can row 24 km/h in still water. When the river is running at 4.8 km/h, it takes him 1 h to row to a place and to come back. How far is the place?

A). 11.52 km

B). 14 km

C). 12.52 km

D). 15 km

8). Sameer can row a certain distance downstream in 24 h and can come back covering the same distance in 36 h. If the stream flows at the rate of 12 km/h, find the speed of Sameer in still water.

A). 30 km/h

B). 15 km/h

C). 40 km/h

D). 60 km/h

9). A sailor sails a distance of 48 km along the flow of a river in 8 h. If It takes 12 h to return the same distance, then the speed of the flow of the river is

A). 0.5 km/h

B). 1 km/h

C). 1.5 km/h

D). 2 km/h

10). Speed of motorboat in still water is 45 km/h. If the motorboat travels 80 km along the stream in 1 h 20 min, then the time taken by it to cover the same distance against the stream will be

A). 4 h 20 min

B). 3 h 40 min

C). 2 h 40 min

D). 2 h 55 min