Question
Train ‘A’ can cross a pole in 6 seconds and a 120
metre long platform in 12 seconds. If the ratio of length of train ‘A’ and train ‘B’ is 2:5, respectively, then find the time taken by train ‘B’ to cross a pole with a speed of 25 m/s.Solution
Let the length and speed of the train ‘A’ be ‘l’ metre and ‘s’ m/s, respectively. According to question, l = 6s Also, 12s = 6s + 120 Or, 6s = 120 Or, s = 20 Therefore, length of train ‘A’ = 6s = 120 metres Length of train ‘B’ = 120 × (5/2) = 300 metres Required time taken = 300 ÷ 25 = 12 seconds
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...Given below are three numbers series I, II and II where each series contains a wrong (odd one out) term. The wrong number in series I, II and III are '...
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