Aptitude - Problems on Trains - Discussion
Discussion Forum : Problems on Trains - General Questions (Q.No. 4)
4.
Two trains running in opposite directions cross a man standing on the platform in 27 seconds and 17 seconds respectively and they cross each other in 23 seconds. The ratio of their speeds is:
Answer: Option
Explanation:
Let the speeds of the two trains be x m/sec and y m/sec respectively.
Then, length of the first train = 27x metres,
and length of the second train = 17y metres.
 |
27x + 17y | = 23 |
| x+ y |
27x + 17y = 23x + 23y
4x = 6y
| |
x | = | 3 | . |
| y | 2 |
Discussion:
233 comments Page 22 of 24.
Mrk said:
8 years ago
Yeah, I got it (x+y) say relative speed.
Diya said:
5 years ago
Very nice explanation, Thanks @Poornima.
Vivek said:
1 decade ago
How the (27x+17y)/x+y=23 formula comes?
RAHAMAN said:
1 decade ago
23-17/27-23=6:4 or 3:2 (LINK-UP METHOD)
Soniya said:
1 decade ago
This is very good method to understand.
UdoNe said:
8 years ago
27x+17y=DISTANCE.
x+y=SPEED,
23=TIME.
x+y=SPEED,
23=TIME.
Md.Mustafijur Rahman said:
6 years ago
s=vt.
t= s/v.
s= distance, v=speed.
t= s/v.
s= distance, v=speed.
Mahesh said:
5 years ago
27+3 = 30.
17+3 = 20.
30/20 = 3:2.
17+3 = 20.
30/20 = 3:2.
Sujata said:
1 decade ago
I agreee with Rohit calculation.
DilipReddy said:
7 years ago
Very clear explanations. Thanks.
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