Question
A boy can swim a certain distance downstream in 2 hours
and return in 5 hours. If the rate of stream is 3 kmph then what is the speed of boy in still water?Solution
Let the speed of the boy in still water be x kmph. Then, (x + 3) × 2 = (x – 3) × 5 => 2x + 6 = 5x - 15 => 3x = 21 => x = 7 kmph
22, 37, 63, 98, 148, ?
24, 42, 60, ?, 96, 114
168, 164, 155, 139, ?, 78
204, 401, 640, ?, 1105, 1406
480, 288, ?, 103.68, 62.208, 37.3248
What will come in place of the question mark (?) in the following series?
75, 219, 388, ?, 809, 106545, 166, 607, 1568, 3249, ?
What will come in place of the question mark (?) in the following series?
45, 66, 44, 67, 43, ?
- What will come in place of the question mark (?) in the following series?
6, 19, 45, ?, 136, 201 150 - 10 × ( 7 - 2)/4 × 8 = ?
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