Aptitude - Boats and Streams - Discussion
Discussion Forum : Boats and Streams - General Questions (Q.No. 9)
9.
A man can row at 5 kmph in still water. If the velocity of current is 1 kmph and it takes him 1 hour to row to a place and come back, how far is the place?
Answer: Option
Explanation:
Speed downstream = (5 + 1) kmph = 6 kmph.
Speed upstream = (5 - 1) kmph = 4 kmph.
Let the required distance be x km.
Then, | x | + | x | = 1 |
6 | 4 |
2x + 3x = 12
5x = 12
x = 2.4 km.
Discussion:
21 comments Page 2 of 3.
Utteya Pal said:
10 years ago
Easiest way to do this kind of problems:
{z(x^2-y^2)}/2x.
Here z= time taken to cover the both distance.
x = speed in still water.
y = speed of current.
{z(x^2-y^2)}/2x.
Here z= time taken to cover the both distance.
x = speed in still water.
y = speed of current.
Kandarp Singh said:
1 decade ago
12 is the lcm of 4 and 6 and that expression solving is correct.
x/6 + x/4 = 1.
(4x+6x)/(6*4) = 1.
(2x+2x)/(3*4) = 1.
2x+3x = 12.
x/6 + x/4 = 1.
(4x+6x)/(6*4) = 1.
(2x+2x)/(3*4) = 1.
2x+3x = 12.
Rishita Burman said:
4 years ago
@Bhima,
You need to find out the L.C.M of the denominators. We multiply the denominator when L.C.M is not possible.
You need to find out the L.C.M of the denominators. We multiply the denominator when L.C.M is not possible.
(1)
Rishita Burman said:
4 years ago
@Bhima,
You need to find out the L.C.M of the denominators. We multiply the denominator when L.C.M is not possible.
You need to find out the L.C.M of the denominators. We multiply the denominator when L.C.M is not possible.
(3)
Sasikumar said:
1 decade ago
Speed downstream = (5 + 1) kmph = 6 kmph.
Speed upstream = (5 - 1) kmph = 4 kmph.
average speed=2(6)(4)/(6+4)
Speed upstream = (5 - 1) kmph = 4 kmph.
average speed=2(6)(4)/(6+4)
Sam said:
1 decade ago
(4x+6x)/(6*4) = 1.
4x+6x = 24.
10x = 24.
x = 24/10.
x = 2.4.
I hope You are all understand.
4x+6x = 24.
10x = 24.
x = 24/10.
x = 2.4.
I hope You are all understand.
(1)
Anil said:
1 decade ago
2x+3x=12
Is that multiplication of 2*3.
If yes, why we have to multiply 2*3 ?
Is that multiplication of 2*3.
If yes, why we have to multiply 2*3 ?
Shantanu datta said:
1 decade ago
From where is this 12 coming from?
2x+3x=6 after the first step.
2x+3x=6 after the first step.
Bhima God said:
1 decade ago
Mul of 6 and 4 should be 24 right?...how that 12 comes?
Dts said:
1 decade ago
Here we take lcm only.
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers