Question
Two trains running in opposite directions cross a pole
in 25 seconds and 15 seconds respectively and they cross each other in 21 seconds.Find the ratio of their speeds?Solution
Let the speeds of the two trains be x m/sec and y m/sec respectively. Then, length of the first train = 25x metres and length of the second train = 15y metres (25x +15y)/(x+y) = 21 25x+15y = 21x + 21y 4x = 6y x/y = 3/2 Therefore, the ratio of their speeds is 3:2.
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