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Two trains running in opposite directions cross a man standing on the platform in 27 seconds and 17

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.
y2

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