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Q:
A) 180 mts | B) 190 mts |
C) 200 mts | D) 210 mts |
Answer: C) 200 mts
Explanation:
Explanation:
Let the length of the train be 'L' mts
let the speed of the train be 'S' m/s
Given it crosses a pole in 10 sec=> L/S = 10 ......(1)
Given it takes 20 sec (double of pole) to cross a platform of length 200 mts
=> (L + 200)/S = 20
=> L/S + 200/S = 20
But from (1) L/S = 10
=> 200/S = 20 - 10
=> S = 20 m/s
Then, from (1)
=> L = 10 x 20 = 200 mts.
Hence, the length of the train = 200 mts.