Question
‘A’ and ‘C’ together can dig a hole in 8 hours
while ‘A’, ‘B’ and ‘C’ together can dig the same hole in 6 hours. Find the time taken by ‘B’ alone to dig the same hole.Solution
Let the total work be 24 units {LCM (8 and 6)}
Efficiency of ‘A’ and ‘C’ together = 24/8 = 3 units/hour
Efficiency of ‘A’, ‘B’ and ‘C’ together = 24/6 = 4 units/hour
Efficiency of ‘B’ = 4 – 3 = 1 unit/hour
Time taken by ‘B’ to dig the same hole alone = (24/1) = 24 hours
35 36 68 207 836 4205
...6 3.5 2.5 ? 8.5 23.75
...16, 54, 128, ‘?’, 432,686
7   24    43    66   ?      126
35    57    101    189    ?     717
130 114 106 102 100 ?
43Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â 44Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â 48Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â ...
If  2  4  6  x  14  28  30
Then, x³+ 2 x+1 = ?
17 ? 33 44 57 72
...35Â Â Â Â Â Â Â Â Â Â 36Â Â Â Â Â Â Â Â Â Â 40Â Â Â Â Â Â Â Â Â Â 49Â Â Â Â Â Â Â Â Â Â 65Â Â Â Â Â Â Â Â Â Â ?
...