Question
A boat takes half time in moving a certain distance
downstream than upstream. What is the ratio between rate in still water and rate of current ?Solution
Let the speed of a boat in still water = ukmph And, speed of current = vkmph Rate downstream = (u+v) kmph Rate upstream =(u−v)kmph Let the distance covered in each case be x km. Then, (2x/u+v) = (x/u−v) 2(u−v) = u+v u = 3v (u/v) = 3:1 Therefore, Required ratio = 3:1
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7, 14, 42, 210, 1470, ?
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It is known that - V₃ = 22 and ...
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112 162 199 ? 242 252
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114 106 102 100 99 ?
...Choose the correct alternative
21: 3 ∷ 574: ?
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