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:
234 comments Page 18 of 24.
Samara said:
8 years ago
Let the distance of platform be x.
Then speed1= x/27-23 and speed2= x/23-17,
So, the ratio of speed is 3:2.
Then speed1= x/27-23 and speed2= x/23-17,
So, the ratio of speed is 3:2.
Pankj said:
8 years ago
One doubt.
According to this answer train taking 27 sec to cross the man having more speed than train taking 17 sec. As per my knowledge train taking more time having less speed anyone can explain this ?
According to this answer train taking 27 sec to cross the man having more speed than train taking 17 sec. As per my knowledge train taking more time having less speed anyone can explain this ?
Sujay said:
8 years ago
---23------>----4-----|27
23<--6sec---|<---17sec----- Man
Train which takes 27 sec to cross a man takes 4 more seconds to cross man(27-23)
Train which takes 17 sec to cross a man takes 6 more seconds to cross train(23-17)
Let distance between crossover of train and man standing to be X
Speed ratio=x/4:x/6.
i,e 3:2.
23<--6sec---|<---17sec----- Man
Train which takes 27 sec to cross a man takes 4 more seconds to cross man(27-23)
Train which takes 17 sec to cross a man takes 6 more seconds to cross train(23-17)
Let distance between crossover of train and man standing to be X
Speed ratio=x/4:x/6.
i,e 3:2.
Pobitro Ghosh said:
8 years ago
Relative time 1st train= 27-23=4,
second train= 23-17=6,
1st:2nd= 6:4=3:2,
Ans:3:2.
second train= 23-17=6,
1st:2nd= 6:4=3:2,
Ans:3:2.
Mayank Yadav said:
8 years ago
(x+y) I am not understanding that where this comes here this question, please give answer.
Sudhan Vybow said:
8 years ago
Make it simple.
27-17 =6 :27-23 =4
6:4 or 3:2.
27-17 =6 :27-23 =4
6:4 or 3:2.
Vishnu said:
7 years ago
@Sudhan.
Isn't 27-17 = 10? How do you say it's 6?
Isn't 27-17 = 10? How do you say it's 6?
Priyesh verma said:
7 years ago
Two trains are moving in opposite direction with the speed of 36 k.m. /h and 54 k.m. /h cross each other in 12 seconds. The length of the 2nd train is half of the 1st train. The 1st train crosses a platform in 1. 30 minutes. Then what is the length of the platform? Please solve this.
Mahesh said:
7 years ago
860m, It consists of two cases.
DilipReddy said:
7 years ago
Very clear explanations. Thanks.
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