Question
The ratio of the boat's speed in still water to the speed
of the stream is given as 12:1. The boat takes a total time in the ratio 13:9 to travel (d + 48) km upstream and (d - 56) km downstream. Determine the value of d.Solution
ATQ;
Let speed of boat in still water and speed of stream is ‘12a’ km/h and ‘a’ km/h respectively.
Upstream speed = 12a – a = 11a km/h
Downstream speed = 12a + a = 13a km/h
So, [(x + 48)/11a]/[(x – 56)/13a] = 13/9
Or, 9x + 432 = 11x – 616
Or, 2x = 1048
Or, x = 524
3 15 35 63 99 ?
15Â Â Â Â Â Â Â Â Â Â Â Â 13 Â Â Â Â Â Â Â Â 28 Â Â Â Â Â Â Â Â Â Â Â Â Â Â 24 Â Â Â Â Â Â Â Â Â Â Â Â Â Â 54 Â Â Â Â Â Â Â Â 52
...6Â Â Â Â Â Â Â Â Â Â Â Â Â 7Â Â Â Â Â Â Â Â Â Â Â Â Â 15Â Â Â Â Â Â Â Â Â Â 46Â Â Â Â Â Â Â Â Â Â 185Â Â Â Â Â Â Â Â ?
...Study the given pattern carefully and select the number that can replace the question mark (?) in it.
4 7 6
15 ? 21
44 68 60
36, 49, 23, 62, ?, 75
6 3.5 2.5 ? 8.5 23.75
...49Â Â Â 84Â Â Â 119Â Â Â 154Â Â Â 189Â Â Â ?
A series is 4, 5, 17, 88, 620, 5585
If another series a, b, 23, d, e, f follows the same pattern as the given number series, then find the approx...
48Â Â Â Â 61 Â Â Â Â 76 Â Â Â Â 94Â Â Â Â 116 Â Â Â Â Â ?
3 12 48 192 768 ?