# Boats and Streams Questions for RRB Group-D PDF

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## Boats and Streams Questions for RRB Group-D PDF

Download Top-10 RRB Group-D Boats and Streams Questions PDF. RRB GROUP-D Boats and Streams questions based on asked questions in previous exam papers very important for the Railway Group-D exam.

Question 1: A boat can cover a distance of 7.2 km downstream and 3.2 km upstream in 2
hours.It can also cover 1.5 km downstream and 0.6 km upstream in 24 minutes. Whatis the
speed of the boat when going downstream (in km/h)?
LATEX

a) Latex 1

b) Latex 2

c) Latex 3

d) Latex 4

Question 2: A boat travels 30 km upstream in 10 hours and travels 52 km downstream in 4 hours. What is the time taken to cover 121 km downstream if the speeds of both stream and boat are decreased by 1 km/hr ?

a) 12 hrs

b) 11 hrs

c) 10 hrs

d) 9 hrs

Question 3: A boat travels 120 km upstream in 6 hours and travels 90 km downstream with double the speed of upstream. What is the time taken to cover the 90km downstream ?

a) 2 hr 10 min

b) 2 hr 15 min

c) 2 hr 20 min

d) 2 hr 30 min

Question 4: A boat at anchor is racked by waves whose consecutive crests are 125 m apart. The velocity of the wave of the moving crests is $25ms^{-1}$, What is the frequency of the rocking of the boat?

a) 0.20 (Hz)

b) 625 (Hz)

c) 250 (Hz)

d) 100 (Hz)

Question 5: A man can row a boat at 10 kmph in still water. If the speed of the stream is 6 kmph, the time taken to row a distance of 80 km down the stream is :

a) 8 hours

b) 5 hours

c) 10 hours

d) 20 hours

Question 6: Speed of a boat in standing water is 9 kmph and the speed of the stream is 1.5 kmph. man rows to a place at a distance of 10.5 km and comes back to the starting point. The total time taken by him is :

a) 1.6 hours

b) 1.8 hours

c) 2.0 hours

d) 2.4 hours

d) Rs. 4500

Instructions

Question 7: A boat takes 4 hours to travel same distance ‘x’ upstream and downstream.If the speed of the boat is 4 km/hr and stream is 2 km/hr then find the value of x ?

a) 6 km

b) 8 km

c) 4 km

d) 10 km

Instructions

Question 8: A boat takes 10 hours to travel same distance ‘x’ upstream and downstream.If the speed of the boat is 10 km/hr and stream is 6 km/hr then find the value of x ?

a) 24 km

b) 28 km

c) 30 km

d) 32 km

Question 9: A boat goes 2 km upstream and 3 km downstream in 45 minutes while it goes 3 km upstream and 9 km downstream in 90 minutes. Whatis the speed (in km/hr) of boat when going down stream?

a) 9

b) 10.5

c) 12

d) 9.5

Question 10: The speed of a boat in still water is 9 km/hr and the speed of stream is 3 km/hr. The difference between the upstream speed and downstream speed will be:

a) 6 km/hr

b) 5 km/hr

c) 3.5 km/hr

d) 7.5 km/hr

let the speed of the boat be ‘b’ and stream be ‘s’.
30/(b-s) =10
b-s=3
52/(b+s) =4
b+s=13
b-s=3
2b=16
b=8 km/hr
s=5 km/hr
Each is decreased by 1 km/hr so
b=7 km/hr
s=4 km/hr
Time taken for 121 km downstream=121/11
=11 hrs

let the speed of the boat be ‘b’ and stream be ‘s’.
120/(b-s) =6
b-s=20
Given b+s=2(b-s)
b+s=2b-2s
3s=b
3s-s=20
2s=20
s=10
b=30
Time taken for 90 km downstream=90/40
=2.25 hrs

Upstream speed =4-2=2 km/hr
Downstream speed=4+2=6 km/hr
Therefore we have $\frac{x}{6}+\frac{x}{2}$=6
4x/6 =4
x=6 km

Upstream speed =10-6=4 km/hr
Downstream speed=10+6=16 km/hr
Therefore we have $\frac{x}{16}+\frac{x}{4}$=10
5x/16 =10
x=32