Question
Two taps would fill a cistern in 18 and 24 minutes
respectively. Both tapsbeing opened find when the Ist tap must be turned off so that the cistern may be just filled in 12 minutes.Solution
AB 1824 72 43 Work done by pipe B in 12 min = 3 × 12 = 36 Remaining work = 72-36 = 36 Time taken by pipe A = 36/4 = 9 min So, the Pipe should be closed after 9 min.
40    42    87    266    ?     5366
14Â Â 16Â Â Â 20Â Â Â 15Â Â 25Â Â Â Â 13Â Â Â 29Â Â Â 9Â Â Â 32Â Â Â 6
...There are three series given below which are following with the same pattern.
Series I: 21, 44, 135, 544, 2725
Series II: 14, B, C, D, E
112    162    199    ?     242    252
...2556   636    156    ?    6
98    219    75    244    ?    273
62 90 122 158 198 ?
50 62 ? 96 126 138
...59, 170, 301, 452, ?, 814
35 36 68 207 836 4205
...
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