Number And Letter Series : Logical Reasoning(Reasoning Aptitude > Logical Reasoning ) Questions and answers for exam Preparation

Reasoning Aptitude > Logical Reasoning

NUMBER AND LETTER SERIES : LOGICAL REASONING MCQs

Number Series, Letter Series

Total Questions : 300 | Page 3 of 30 pages

Question 21. Direction To Solve : Find out the wrong term in the given Number Series.
8, 27, 125, 343, 1331

8
343
1331
125
None of these

Discuss Question

Answer: Option D. -> 125
- The numbers are cubes of prime numbers i.e. 2, 3, 5, 7 hence none of the option is wrong.

Question 22. Direction To Solve : Find out the wrong term in the given Number Series.
10, 14, 28, 32, 64, 68, 132

28
32
64
132
None of these

Discuss Question

Answer: Option D. -> 132
- Alternately, the numbers are increased by four and doubled to get the next number Thus (10 + 4 =14, 14 x 2 = 28), (28 + 4 = 32, 32 x 2 = 64) and so on. So 132 is wrong and must be replaced by (68 x 2) = 136

Question 23. Direction To Solve : Find out the wrong term in the given Number Series.
1, 5, 5, 9, 7, 11, 11, 15, 12, 17

11
12
17
15
None of these

Discuss Question

Answer: Option B. -> 12
- The given sequence is a combination of two series (1) 1, 5, 7, 11, 12 and (2) 5, 9, 11, 15, 17 The pattern in both Ithe series is +4, +2, +4,+2 So 12 is wrong and replaced by (11 + 2) = 13

Question 24. Direction To Solve : Find out the wrong term in the given Number Series.
11, 2, 21, 3, 32, 4, 41, 5, 51, 6

21
11
32
51
None of these

Discuss Question

Answer: Option C. -> 32
- The given sequence is a combination of two series (1) 11, 21, 32, 41, 51 and (2) 2, 3, 4, 5, 6 The pattern in the first series is +10. So 32 is wrong and must be replaced by (21 + 10) = 31

Question 25. Direction To Solve : Find out the wrong term in the given Number Series.
11, 5, 20, 12, 40, 26, 74, 54

5
20
40
26
None of these

Discuss Question

Answer: Option C. -> 40
- The given sequence is a combination of two series (1) 11, 20, 40, 74 and (2) 5, 12, 26, 54 The pattern in first series is +9, +18, +36, …. so 40 should be replaced by 38. So 40 is wrong

Question 26. Direction To Solve : Find out the wrong term in the given Number Series.
56, 72, 90, 110, 132, 150

72
90
110
150
None of these

Discuss Question

Answer: Option D. -> 150
- The numbers are 7 x 8, 8 x 9, 9 x 10, 10 x 11, 11 x 12, 12 x 13. So 150 is wrong and replaced by (12 x 13) = 156

Question 27. Direction To Solve : Find out the wrong term in the given Number Series.
89, 78, 86, 80, 85, 82, 83

83
82
86
78
None of these

Discuss Question

Answer: Option C. -> 86
- The sequence is -11, +9, -7, +5, -3, +1. So 86 is wrong and must be replaced by (78 + 9) = 87

Question 28. Direction To Solve : Find out the wrong term in the given Number Series.
25, 36, 49, 81, 121, 169, 225

36
49
69
225
None of these

Discuss Question

Answer: Option A. -> 36
- The correct sequence is 52, 72, 92, 112, 132, 152. So, 36 is wrong.

Question 29. Direction To Solve : Find out the wrong term in the given Number Series.
2, 5, 10, 17, 26, 37, 50, 64

17
26
37
64
None of these

Discuss Question

Answer: Option D. -> 64
- The numbers are 12 + 1, 22 + 1, 32 + 1 and so on. So 64 is wrong. The correct term is (82 + 1 ) i.e. 65

Question 30. Direction To Solve : Find out the wrong term in the given Number Series.
1, 5, 9, 16, 25, 37, 49

9
16
25
37
None of these

Discuss Question

Answer: Option B. -> 16
- The given sequence is a combination of two series (1) 1, 9, 25, 49 and (2) 5, 15, 37 The pattern in first series is +8, +16, +24. The pattern second series is 22 + 1, 42 + 1, 62 + 1 So 16 is wrong and must be replaced by 42 + 1 i.e 17