# Important Series for IBPS Clerk /RBI Assistant 2017

## Important Series for IBPS Clerk /RBI Assistant 2017

Directions (Q.1-10) : Find the number in place of question mark (?) in the following number series ?
1. 3  81  ?  1029  2187  3993
1) 375
2) 648
3) 192
4) 575
5) 243
2. 30  45  75  105  165  ?
1) 185
2) 205
3) 215
4) 195
5) 230
3.  8   24  12  36  18  54  ?
1) 64
2) 79
3) 34
4) 37
5) 27
4.  4320   720   144   ?   12   6   6
1) 56
2) 60
3) 26
4) 36
5) 16
5.  26   63   124   215   342   ?
1) 511
2) 509
3) 504
4) 515
5) 525
6.  27   370   1099   2430   4627   ?
1) 8002
2) 8004
3) 8006
4) 8008
5) 8010
7.  15   66   321   1596   7971   ?
1) 39842
2) 39844
3) 39846
4) 39848
5) 39850
8.  117   365   861   1853   3837   ?
1) 7801
2) 7802
3) 7803
4) 7804
5) 7805
9.  6  21   101   601   4201   ?
1) 33601
2) 33602
3) 33603
4) 33604
5) 33605
10. 232   360   530   748   1020   ?
1) 1350
2) 1352
3) 1354
4) 1356
5) 1358

Answers:
1. 1; The series is   13 × 3, 33 × 3, 53 × 3, 73 × 3,……….
2. 4; Each number is a prime number multiplied by 15. Thus the series is
15 × 2, 15 × 3, 15 × 5, 15 × 7, 15 × 11,………
3. 5; The series is ×3, ÷2, ×3, ÷2,……
4. 4; The series is ÷6, ÷5, ÷4, ÷3,…….
5. 1; The series is (33 – 1), (43 – 1), (53 – 1), (63 – 1), (73 – 1),…
6.  1; The series is 27
27 + 73 = 370
370 + 93 = 1099
1099 + 113 = 2430
2430 + 133 = 4627
4627 + 153 = 8002
7. 3; The series is ×5 – 9, ………
8. 5; The series is +248, +496, +992, +1984,……
9. 1; The series is ×4 – 3, ×5 – 4, ×6 – 5, ……….
10. 2; The series is 63 + 16, 73 + 17, 83 + 18, 93 + 19,……..

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