Question
Train A running at speed of 45 km/hr crosses a platform
having twice the length of train in 12 sec. Train B whose length is 260m crosses same platform in 18 sec, then find the speed of train B ?Solution
Let length of train A = x Length of platform = 2x Speed = distance/time ⇒ 45 x 5/18 = (x + 2x)/12 ⇒ x = 50 m = length of train A Length of platform = 50 x 2 = 100m For train B, Speed = distance/time ⇒ (100 + 260)/18 x (18/5) ⇒ 72 km/hr
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