Aptitude - Boats and Streams - Discussion
Discussion Forum : Boats and Streams - General Questions (Q.No. 2)
2.
A man's speed with the current is 15 km/hr and the speed of the current is 2.5 km/hr. The man's speed against the current is:
Answer: Option
Explanation:
Man's rate in still water = (15 - 2.5) km/hr = 12.5 km/hr.
Man's rate against the current = (12.5 - 2.5) km/hr = 10 km/hr.
Discussion:
72 comments Page 7 of 8.
Ahamed Kabeer said:
4 years ago
Thank you everyone for explaining this.
Meenakshi said:
4 years ago
What is still water and current speed?
(2)
Himanth said:
4 years ago
Here time has given 8hr 48min upstream, 4 hours downstream.
T=8 4/5 (While changing min to hours 48/60=4/5)
Upstream speed = Distance/time.
x-y = D/8.4/5.
D = 44/5(x-y)-------> (1)
Now downstream speed=Distance/time.
X+y=D/4,
D=4(X+y) -----------> (2)
Equate eq 1 and 2.
44/5(x-y) = 4(X+y).
24x = 64y.
X/y = 64/24,
X/y = 8:3.
T=8 4/5 (While changing min to hours 48/60=4/5)
Upstream speed = Distance/time.
x-y = D/8.4/5.
D = 44/5(x-y)-------> (1)
Now downstream speed=Distance/time.
X+y=D/4,
D=4(X+y) -----------> (2)
Equate eq 1 and 2.
44/5(x-y) = 4(X+y).
24x = 64y.
X/y = 64/24,
X/y = 8:3.
(1)
Arun said:
4 years ago
Hey guys.
If they said the man speed is ..the answer is 12.5...but;
The man speed with the current.
So the 15 km/hr have ( man speed + Current speed).
So the answer is 10km/hr.
If they said the man speed is ..the answer is 12.5...but;
The man speed with the current.
So the 15 km/hr have ( man speed + Current speed).
So the answer is 10km/hr.
(3)
Rathod Vamshi said:
4 years ago
Here, the given speed of the man 15 km/hr but not given directly speed of the man 15 km/hr then we subtract 15-2.5 then we get the speed of the man.
(3)
Anonymous said:
4 years ago
@All.
Suppose you are riding a boat which is arriving to the beach. Naturally, the waves are in the same direction of your boat. Dont you feel easy to drive it then. Hence, the speed of waves/current supplement your boat speed. Then, it is called going downstream or going with the waves/current. Hence, By thinking vice-versa we know that we'd have to subtract the speed of the stream
Suppose you are riding a boat which is arriving to the beach. Naturally, the waves are in the same direction of your boat. Dont you feel easy to drive it then. Hence, the speed of waves/current supplement your boat speed. Then, it is called going downstream or going with the waves/current. Hence, By thinking vice-versa we know that we'd have to subtract the speed of the stream
(2)
Ayaan mansoori said:
3 years ago
Yes, you are right. Thanks @Balaji.
(1)
Tejas said:
3 years ago
Yes, you are right @Balaji.
Good Explanation, Thanks a lot.
Good Explanation, Thanks a lot.
(3)
Chala Alemu Feyisa said:
3 years ago
I am not understanding this. Please explain me.
(3)
Keerthana said:
3 years ago
You are right @Balaji.
Thank you for explaining.
Thank you for explaining.
(6)
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