Solution NUMBER SERIES PROBLEMS ASKED IN PO EXAMS FOR SBI PO, BANK PO, IBPS PO Set 1

1.  (3) The given series is based on the following pattern:
30 = 12 × 6 – 7 × 6
120 = 30 × 5 – 6 × 5
460 = 120 × 4 – 5 × 4
1368 = 460 × 3 – 4 × 3
2730 = 1368 × 2 – 3 × 2
Similarly,
(a) = 16 × 6 – 7 × 6 = 96 – 42 = 54
(b) = 54 × 5 – 6 × 5 = 240
(c) = 240 × 4 – 5 × 4 = 940
(d) = 940 × 3 – 4 × 3 = 2808
Hence, 2808 will come in place of (d)
2
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3.

4.

5.

6. (1) The given series is based on the following pattern :
1 = 1³      8 = 2³    27 = 3³      64 = 4³    125 = 5³
Hence, 8 will come in place of the question mark

7. (5) The given series is based on the following pattern :
25 = 5²      16 = 4²    9 = 3²      4 = 2²    1 = 1²
Hence, 9 will come in place of the question mark

8. (1) The given series Is based on the following pattern:
1 × 2 + 2 × 2 = 6
6 × 4 + 4 × 3 = 36
36 × 6 + 6 × 4 = 240
240 × 8 + 8 × 5 = 1960
1960 × 10 + 10 × 6 = 19660
Hence, 19660 will come in place of the question mark.

9
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10.  (2) The given series is based on the following pattern :
2 + 5 = 7            7 + 5 = 12
12 + 7 = 19       19 + 12 = 31
31 + 19 = 50     50 + 31 = 81