Question
If the diameter of a wire is decreased by
10%, by how much percent (approximately) will the length be increased to keep the volume constant ?Solution

21 23 26 ? 39 51
...24 47 137 ? 2679 16049
...48   50   54   57   ?   70
10 625 50 125 250 25 ?
...Find the 31st term of the series 25, 29, 33……
640 320 160 ? 40 20
261Â Â Â Â Â 256Â Â Â Â Â Â 246Â Â Â Â Â Â 231Â Â Â Â Â 211Â Â Â Â Â ?
...4, 8, 24, ?, 840, 9240
45    47    97    296    ?     5966
The following numbers form a series followed by a (?). Find the odd one out first and then find that what will come in place of the question mark (?) ac...