# COGNIZANT Coding pattern and Number series pattern recognition Questions with Answers

1. 1, 6, 13, 22, 33,

A. 35
B. 36
C. 48
D. 49
:B .

Justification:
The numbers are  12, 22, 32, 42, 52.
.’. Missing number = 6= 36.

2. 20, 19, 17, x , 10, 5
A. 12
B. 13
C. 14
D. 15
Justification:
The Pattern is  – 1, – 2,…
.’. Missing number = 17 – 3 = 14.

3. 2, 3, 5, 7, 11, x, 17

A. 12
B. 13
C. 14
D. 15
Justification:
Clearly, the given series consists of prime numbers starting from 2. The prime number after 11 is 13.
So, 13 is the missing number.

4. 6, 11, 21, 36, 56,
A. 42
B. 51
C. 81
D. 91
Justification:
The pattern is + 5, + 10, + 15, + 20,….
.’. Missing Number = 56 + 25 = 81

5. 1, 6, 13, 22, 33,
A. 44
B. 45
C. 46
D. 47
Justification:
The pattern is + 5, + 7, + 9, + 11,…
.’. Missing number = 33 + 13 = 46.

6. 3, 9, 27, 81,
A. 324
B. 243
C. 210
D. 162
Justification:
Each term of the given series is obtained by multiplying its preceding term by 3.
.’. Missin number = 81 * 3 = 243.

7. 1, 9, 17, 33, 49, 73,
A. 97
B. 98
C. 99
D. 100
Justification:
The pattern is + 8, + 8, + 16, + 24,….
.’. Missing number = 73 + 24 = 97

8. 2, 5, 9, , 20, 27
A. 14
B. 16
C. 18
D. 24
Justification:
The pattern is + 3, + 4,….
.’. Missing number = 9 + 5 = 14.

9. 5, 9, 17, 29, 45,
A. 60
B. 65
C. 68
D. 70
Justification:
The pattern is + 4, + 8, + 12, + 16, …
.’. Missing number = 45 + 20 = 65.

10. 3, 7, 15, 31, 63,
A. 92
B. 115
C. 127
D. 131
Justification:
Each number in the series is the preceding number multiplied by 2 and then increased by 1.
Thus, (3 * 2) + 1 = 7,
(7 * 2) + 1 = 15,
(15 * 2) + 1 = 31 ans so on.
.’. Missing number = (63 * 2) + 1 =127.

11. U, O, I, ?, A
A. E
B. C
C. S
D. G
Justification:
The series consists of vowles A, E, I, O, U written in a reverse order

12. Y, W, U, S, Q, ?, ?
A. N, J
B. M, L
J, R
C. L, M
D. O, M
Justification:
The series consits of alternate letters in reverse order.

13. A, B, D, G, ?
A. M
B. L
C. K
D. H
Justification:
The first, second, third,…. letters of the series are respectively moved one, two, three,… steps forward to obtain the seccessive terms.

14. Z, U, Q, ?, L

A. I
B. K
C. M
D. N
Justification:
The first, second, third,… letters of the series are respectively moved one, two, three,… steps forward to obtain the successive terms.

15. A, C, F, H, ?, M

A. L
B. K
C. J
D. I
Justification:
The letters  are alterntely moved two and three steps forward to obtainthe successive terms.

16. G4T, J10R, M20P, P43N, S90L
A. G4T
B. J10R
C. M20P
D. P43N E.S90L
Justification:
The first letter of each term is moved three steps forward and
the last letter is moved two steps backward to obatin the corresponding letters of the next term.
The numbers follow the sequence x 2 + 1, x 2 + 2, x 2 + 3, x 2 + 4.
So, 10 is wrong and must be replaced by (4 x 2 + 1)  i.e. 9.

17_ _ aba _ _ ba _ ab
abbbaAbbabBaabbBbaba
B . abbab
Justification:
The series is ab / ab / ab / ab / ab / ab.
Thus, the pattern ab is repeated.

18. ab _ _ _ b_ bbaa _

A. abaab
B. Abbab
C. Baaab
D. Babba
Justification:
The series is abb / aab / abb / aab.
Thus, the pattern abb, aab is repeated.

19. _ baa _ aab _ a _ a
A. aabb
B. Aaba
C. Abab
D. Baab