Question
Find the wrong number in the given number series.
2, 5, 11, 23, 47, 97Solution
Pattern: each term = (previous term × 2) + 1 2 → 2×2+1 = 5 5 → 5×2+1 = 11 11 → 11×2+1 = 23 23 → 23×2+1 = 47 47 → 47×2+1 = 95 So last term should be 95, not 97. Wrong term = 97
Select the number from among the given options that can replace the question mark (?) in the following series.
2, 6, 12, 20, ?, ?
92,  51,  21,  13.5,  x,  4.25
find the value of (10x + x -5)?
504 625 769 938 1134 ?
...5 4 29 24 185 ?
102, 246, 442, 698, 1022, ?
Find the odd one out: 11, 13, 17, 19, 21
Find sum of first n terms: 2 + 6 + 12 + 20 + 30 + …
D irection: Which of the following will replace ‘?’ in the following series
10,14,’?’,199, 352, 530
...If 2.5 3.5 x 30 124 625
Then, x ² - 1 - 2x = ?
...6   16  ?     244  1,245  7,506  52,591
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