Question
Time is taken by two trains running in opposite
directions to cross a man standing on the platform in 24 seconds and 14 seconds respectively. It took 20 seconds for the trains to cross each other. What is the ratio of their speeds?Solution
Let the speed one train be x m/s and the speed of the second train be y m/s. Length of the first train = Speed × Time = 24x Length of second train = Speed × Time = 14y So, {(24x + 14y)/(x+y)} = 20 ⇒  24x + 14y = 20x + 20y ⇒ 4x = 6y Therefore, x:y = 3:2
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1528, 1416, 1204, ?, 480, -32
143 Â Â Â Â 119Â Â Â Â 107Â Â Â Â 101Â Â Â Â Â 98Â Â Â Â ?
96 89 ? 90 94 91
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What will come in place of the question mark (?) in the following series?
305...
In each of the following number series, one term is missing. Find the missing term.
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What will come in place of the question mark (?) in the following series?
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7 29 61 ? 211 349
...
