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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:


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:
A. 1 : 3B. 3 : 2
C. 3 : 4D. None of these


Answer: Option B
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
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