Question
A motorboat in still water travels at a speed of 40
km/hr. It goes 45 km upstream in 2 hour 15 minutes. The time taken by it to cover the same distance down the stream will be :Solution
Speed of the motorboat upstream = 45/(9/4) = 20 km/hr Let the speed of the current be x km/hr ⇒ 40 – x = 20 ⇒ x = 20 km/hr Speed of motor boat downstream = 40 + 20 = 60 km/hr Time taken to cover 45 km at 60 km/hr = 45/60 = 3/4 hours or 45 minutes
56. 23Â Â Â Â Â 45Â Â Â Â Â 89Â Â Â Â Â 177Â Â Â Â Â 363Â Â Â Â Â 705
...625, 5, 125, 25, 25, ? , 5
There are three series given below which are following with the same pattern.
Series I: 9, 10, 32, 163, 1145
Series II: 4, B, C, D, E
...5 14 56 220 1125 6786
...2,0, 9, 20, ‘?’, 714
7 29 ? 129 211 349
25Â Â Â Â Â Â Â Â Â Â 34Â Â Â Â Â Â Â Â Â Â 61Â Â Â Â Â Â Â Â Â Â 106Â Â Â Â Â Â Â Â 169Â Â Â Â Â Â Â Â ?
...9 10 6 15 -1 ?
...22   39    58    81   ?      141
The question below is based on the given series I. The series I satisfy a certain pattern, follow the same pattern in series II and answer the questions...