Practice Quantitative Aptitude Questions For IBPS RRB 2017 (Number Series):
Dear Readers, Important Practice Aptitude Questions for IBPS RRB Exams 2017 was given here with Solutions. Aspirants those who are preparing for the Bank Examination and other Competitive Examination can use this material.
Directions (Q. 1-5): In each of these questions a number series is given. In each series only one number is wrong. Find out the wrong number.
1).  50,   51,    47,   56,   42,   65,   29
- Â 51
- 47
- Â 56
- 42
- Â 65
2).  3,  9,  23,  99,  479,  2881,  20159
- 9
- 23
- 99
- Â 479
- Â 2881
3).   7,   4,   6,   9,   20,   52.5,   160.5
- Â 6
- Â 4
- 20
- 9
- 52.5
4).  1,   3,   6,  11,   20,   39,   70
- 3
- Â 39
- Â 11
- Â 20
- 6
5).   2,   13,   27,   113,   561,   3369,   23581
- Â 27
- 13
- Â 113
- 561
- 3369
Directions (Q. 6-10): What should come in place of question mark (?) in the following number series:
6).  17,  9,  15,  40,  143.5,  ?
- Â 505.75
- Â 578.5
- Â 650.25
- 578
- Â 678.5
7).  3,  5,  13,  49,  241,  ?
- Â 1210
- 1451
- Â 1221
- Â 1441
- Â 1200
8).  508,  256,  130,  67,  35.5,  ?
- 18.25
- 19.75
- 17.25
- 15.75
- Â 17.75
9).   7,  13,  31,  85,  247,  ?
- 409
- 727
- 733
- 649
- 444
10).  64,  36,  22,  15,  ? 9.75
- 11
- 12
- 11.5
- 11.75
- 10
Explanation With Answer Key:
- The series is 50 + 1^2 = 51, 51 – 2^2 = 47, 47 + 3^2 = 56, 56 – 4^2 = 40, 40 + 5^2 = 65, 65 – 6^2 = 29.
Hence, there should be 40 in place of 42.
Answer is: d)
- The series is 3 × 2 + 3 = 9, 9 × 3 – 4 = 23, 23 × 4 + 5 = 97, 97 × 5 – 6 = 479, 479 × 6 + 7 = 2881, 2881 × 7 – 8 = 20159
Hence, there should be 97 in place of 99.
Answer is: c)
- The series is x0.5 + 0.5, x1 + 1, x 1.5 + 1.5, x 2 + 2, x 2.5 + 2.5, x 3 + 3…
Hence, there should be 5 in place of 6.
Answer is: a)
- The series is 1 × 2 + 1 = 3, 3 × 2 + 0 = 6, 6 × 2 – 1 = 11, 11 × 2 – 2 = 20, 20 × 2 – 3 = 37, 37 × 2 – 4 = 70.
Hence, there should be 37 in place of 39.
Answer is: b)
- The series is 2 × 2 + 7 = 11, 11 × 3 – 6 = 27, 27 × 4 + 5, = 113, 113 × 5 – 4 = 561, 561 × 6 + 3 = 3369, 3369 × 7 – 2 = 23581.
Hence, there should be 11 in place of 13.
Answer is: b)
- The series is ×0.5 + 0.5, ×1.5 + 1.5, ×2.5 + 2.5, ×3.5 + 3.5, ×4.5 + 4.5
Answer is: c)
- The series is ×2-1, ×3-2, ×4-3, ×5-4, ×6-5
Answer is: d)
- The whole series is /2 + 2
Answer is: b)
- The series is +3 × 2, +3 × 6, +3 × 18, +3 × 54, +3 × 162
Answer is: c)
- The whole series is ×0.5 + 4
Answer is: c)