Subject
Quantitative Aptitude
Topic
Speed & Distance
A 310 metres long train, travelling at a uniform speed, crosses a platform in 46.5 seconds and a man standing on the platform in 31 seconds. What is the length of the platform?
A 310 metres long train, travelling at a uniform speed, crosses a platform in 46.5 seconds and a man standing on the platform in 31 seconds. What is the length of the platform?
ক)
124 metresখ)
93 metresগ)
310 metresঘ)
Cannot be determinedঙ)
None of theseExplanation
Let the length of the platform = x metres When a train crosses a platform, Total distance covered = Length of the train + Length of the platform Thus, total distance = 310 + x ---(1) Total time taken = 46.5 seconds (given) ---(2) When a train crosses a man, Total distance travelled = Length of the train Thus, total distance = 310m ---(3) Total time taken = 31 seconds (given) ---(4) Now, Average speed = (Total Distance Travelled)/(Total Time taken) ∴ From 1 and 2, Average speed = (310 + x)/46.5 ---(5) From 3 and 4, Average speed = 310/31 = 10m/s ---(6) Equating 5 and 6, ⇒ 310 + x = 465 ⇒ x = 155m Thus, length of the platform is 155m.Related questions
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