Question
A train can cross a pole, a bridge of 510 meter long and
platform of 480 meter long in 15 seconds, _____ seconds and 31 seconds, respectively. The value given in which of the following option will fill the blank to make the above statement true:Solution
Let the length of the train = x meter So according to question: x/15 = (x + 480)/31 31x = 15x + 7200 16x = 7200 x = 450 So the length of the train = 450 m Speed of the train = 450/15 = 30 m/s Time taken by the train to cross a bridge 510 meter long = (450 + 510)/30 = 960/30 = 32 seconds
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