# Quantitative Aptitude: Boats and Streams Set 1

Boats and Streams Bank PO Questions

1. Vimal can row a certain distance downstream in 14 hoursand return the same distance in 21 hours. If the speed of the stream is 6 kmph, Find the speed of Vimal in the still water?
A) 21 kmph
B) 15 kmph
C) 30 kmph
D) 35 kmph
E) None of these
Option C
Solution:

Speed of Vimal in still water = x
Downstream Speed = (x + 6)
Upstream Speed = (x – 6)
Downstream Distance = Upstream Distance
14(x + 6) = 21(x – 6)
2x + 12 = 3x – 18
x = 30 kmph.
2. Rahul can row a certain distance downstream in 12 hour and return the same distance in 18 hour. If the speed of Rahul in still water is 12 kmph, find the speed of the stream?
A) 2.1 kmph
B) 1.5 kmph
C) 4.4 kmph
D) 2.4 kmph
E) None of these
Option D
Solution:

Let the speed of the stream be x kmph
Down stream = (12+x)
Up stream = (12−x)
suppose the distance traveled be y
y/(12+x) = 12 —(1)
y/(12−x)= 18 —-(2)
From eqn (1) and (2)
x= 2.4 kmph
3. Anil can row 18 kmph in still water and he finds that it takes him twice as long to row up as to row down the river. Find the rate of stream?
A) 5 kmph
B) 6 kmph
C) 4 kmph
D) 3 kmph
E) None of these
Option B
Solution:

Stream Speed = a kmph
Time Taken = x km
Downstream speed = (18 + a) kmph
Upstream speed = (18 – a) kmph
Time taken to travel downstream = 2 * Time taken to travel upstream
(18 + a) / x = 2(18 + a) / x
18 + a = 36 – 2a
3a = 18
a = 6 kmph
OR USE FORMULA
Speed of boat = [tu+td]/[tu-td] * Speed of stream
So 18 = [2x + x]/[2x – x] * Speed of stream
4. Mr. Suresh can row to a place 48 km away and come back in 14 hours. He finds that he can row 4 km with the stream in the same time as 3 km against the stream. The rate of the stream is?
A) 1 kmph
B) 3 kmph
C) 4 kmph
D) 6 kmph
E) None of these
Option A
Solution:

Downstream speed = 4/x kmph
upstream speed = 3/x kmph
48/(4/x) + 48/(3/x) = 14
Solving we get x = 1/2 kmph
So, Speed of downstream = 8 kmph, Speed of upstream = 6 kmph
Stream Speed = 1/2(8 – 6) kmph = 1 kmph
5. Mr.Ramesh’s speed with the current is 20 kmph and the speed of the current is 5 kmph. Ramesh’s speed against the current is?
A) 15 kmph
B) 19 kmph
C) 17 kmph
D) 10 kmph
E) None of these
Option D
Solution:

Ramesh’s speed with the current = 20 kmph
=> Ramesh’s speed + speed of the current = 20 kmph
Speed of the current = 5 kmph
Speed of Ramesh = 20 – 5 = 15 kmph
Ramesh’s speed against the current = speed of Ramesh – speed of the current = 15 – 5 = 10 kmph
6. Ravi can row 12 kmph in still water when the river is running at 6 kmph it takes him 1 hour to row to a place and to come back. How far is the place?
A) 5.5 km
B) 4.5 km
C) 8.2 km
D) 4.2 km
E) None of these
Option B
Solution:

Downstream Speed = 18 kmph
Upstream Speed = 6 kmph
Distance = x
x/18 + x/6 = 1
18x + 6x = 108
24x = 108
x = 4.5 km
OR USE FORMULA:
Distance = time [B2 – R2]/2*B
So distance = 1 * [122 – 62]/2*12
Distance = 108/24 = 4.5 km
7. The different between downstream speed and upstream speed is 2 kmph and the total time taken during upstream and downstream is 2 hours. What is the upstream speed, if the downstream and upstream distance are 2 km each?
A) 5.2 kmph
B) 3.7 kmph
C) 2.8 kmph
D) 1.4 kmph
E) None of these
Option D
Solution:

2/x + 2/(x+2) = 2.
x2 – 2 = 0
x = 1.414kmph
8. Rani can row 8 kmph in still water. If the river is running at 4 kmph it takes 90 minutes to row to a place and back. How far is the place?
A) 4.5 km
B) 8.2 km
C) 4.2 km
D) 3.5 km
E) None of these
Option A
Solution:

Speed in still water = 8 kmph
Speed of the stream = 4 kmph
Upstream Speed = (8-4) = 4 kmph
Downstream Speed = (8+4) = 12 kmph
Total time = 90 minutes = 90/60 = 3/2 hrs
Let x is the distance
x/12 + x/4 = 3/2
x = 4.5 km
9. Sumi can swim 6 kmph in still water. If the velocity of the stream be 2 kmph, the time taken by her to swim to a place 24 km upstream and back, is?
A) 6 hours
B) 5 hours
C) 4 hours
D) 8 hours
E) 9 hours
Option E
Solution:

Upstream speed = speed of man – speed of stream=6 – 2 = 4
Downstream speed = speed of man + speed of stream=6 + 2=8
Time taken to go upstream = distance/speed = 24/4 =6 hour
Time taken to go downstream = distance/speed =24/8 = 3 hour
Total time =6+3 = 9 hour
10. Raghu can row 96 km downstream in 8 hours. If the speed of the current is 3 kmph, then find in what time will be able to cover 12 km upstream?
A) 6 hours
B) 5 hours
C) 4 hours
D) 8 hours
E) 2 hours
Option E
Solution:

Downstream speed = 96/8 = 12 kmph
Speed of current = 3 kmph
Speed of kamal in still water = 12-3 = 9 kmph
Upstream speed = 9-3 = 6 kmph
Time taken to cover 12 km upstream 12/6 = 2 hours

## 20 Thoughts to “Quantitative Aptitude: Boats and Streams Set 1”

1. C®u\$h the Competition

starting hi galat ans. se 🙁 mod ans is 48

1. Shubhra

Ohh. Yes
Take the second time as 21 hrs

2. Ayushi Srivastava

3. Revolver Rani

Where can we get DI based on Boats and streams and on other chapters as well?

1. Shubhra

check sets 34 to 43

http://aspirantszone.com/data-interpretation/

1. karthik

mam plz help me to clarify the 2nd question answer. i used to solve 2nd question same like 1st one but urs approaching was diff…y?

1. Shubhra

where is the approach different ?
Both are solved using downstream and upstream speeds

May be I am not getting your query

1. karthik

mam in 1st: 14(x + 6) = 21(x – 6) this approach..
2nd: 12(12+x) = 18(12-x)
i was used same approach for 2nd one..(i think in 2nd question suresh nd rahul two persons..).

2. Shubhra

ok ok

yes same approach can be followed

3. karthik

but i got wrong answer. mam

4. PHENOMENAL

thanx upload more on boats and streams high level

5. komal

1 & 2 No. Kaise kiya apne?

2. karthik

using suresh nd rahul’s speeds..

3. komal

Mam in 10th question…
Current Ka speed diya he matlab”y” Ka speed 3 diya he and upstream means x-y =12 diya he ,so isse agar X ki value nikal no ho to equation
X-y=12
X-3=12
X=15 hoga…. Yaha iss equation se 12-3=9 kaise hua plz explain
And correct me where I’m wrong!

4. PHENOMENAL

maam 7 ques me x and x-2 hoga shayd

4. kumkum ahuja

thanku az ::)

1. kumkum ahuja

again 😛

1. kumkum ahuja

again 😛

5. Nishu

thanks

6. jk

okkk