Question
Train A running at speed of 81 km/hr crosses a platform
having twice the length of train in 12 sec. Train B whose length is 360m 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 ⇒ 81 x 5/18 = (x + 2x)/12 ⇒ x = 90 m = length of train A Length of platform = 90 x 2 = 180m For train B, Speed = distance/time ⇒ (180 + 360)/18 x (18/5) ⇒ 108 km/hrÂ
Direction: Which of the following will replace ‘?’ in the given question?
2, ‘?’, 46, 136, 311, 605, 1086
8 9 30 155 ? 9837 108218
...60  61  126  387  ?   7845
31Â Â Â 32Â Â Â Â 41Â Â Â Â 66Â Â Â 115Â Â Â Â ?
45    47    97    296    ?     5966
38 18 16 28 ? 816
6000 3002 1503 ? 378.75 191.375 97.6875
...18Â Â Â Â Â Â Â Â Â Â 434Â Â Â Â Â Â Â Â 642Â Â Â Â Â Â Â Â 746Â Â Â Â Â Â Â Â 798Â Â Â Â Â Â Â Â ?
...12, 16, 25, 41, 66, ?
10 625 50 125 250 25 ?
...
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