Number Series – Part 2 | Find the Missing Number: 20 General Intelligence Questions

 Welcome to Part 2 of our Number Series practice series! This set contains 20 new missing-number questions designed to strengthen your numerical reasoning, pattern recognition, and analytical thinking skills.

Observe each number series carefully, identify the underlying pattern, and determine the missing number. The questions include a variety of logical patterns to keep your problem-solving skills sharp.

These questions are ideal for General Intelligence, Mental Ability, Olympiad, scholarship, and competitive exam preparation.

Can you solve all 20 questions without looking at the answers? Give it a try!

Number Series Mastery: Set 2

Explore 20 brand-new logical patterns—including product of digits, factorials, alternating operations, and digit reversals. Click an option for instant feedback!

Question 1: Digit Product Addition (+ Product of Digits)

12

14

18

26

?

(A) 34

(B) 36

(C) 38

(D) 40

Question 2: Prime Squares Pattern (p²)

4

9

25

49

?

(A) 81

(B) 121

(C) 100

(D) 144

Question 3: Triangular Difference Pattern (+1, +3, +6, +10...)

5

6

9

15

25

?

(A) 35

(B) 36

(C) 38

(D) 40

Question 4: Factorial Sequence (n!)

1

2

6

24

120

?

(A) 720

(B) 600

(C) 840

(D) 5040

Question 5: Tribonacci Sequence (Sum of Previous 3 Terms)

1

1

2

4

7

13

?

(A) 22

(B) 24

(C) 26

(D) 20

Question 6: Multiply and Decrement (×2 - 1, ×2 - 2, ×2 - 3...)

3

5

8

13

22

?

(A) 35

(B) 37

(C) 39

(D) 41

Question 7: Replaced Digit Reverse Sequence

13

31

17

71

19

?

(A) 91

(B) 81

(C) 93

(D) 23

Question 8: Cubes Minus Consecutive Primes (n³ - prime_n)

-1

5

22

57

?

(A) 110

(B) 118

(C) 120

(D) 114

Question 9: Alternating Powers (2ⁿ, 3ⁿ, 2ⁿ, 3ⁿ...)

2

3

4

9

8

27

?

(A) 12

(B) 16

(C) 64

(D) 32

Question 10: Half-Step Decrease & Increase (×0.5 + 0.5, ×1 + 1...)

8

4.5

5.5

9.75

?

(A) 18.5

(B) 20.75

(C) 21.5

(D) 22.25

Question 11: Powers of 2 Minus 3 (2ⁿ - 3)

-1

1

5

13

29

?

(A) 61

(B) 57

(C) 59

(D) 63

Question 12: Sum of Digits Multiplied by 3

12

9

27

27

?

(A) 18

(B) 24

(C) 27

(D) 81

Question 13: Alternating Sign Arithmetic (+10, -5, +20, -10...)

10

20

15

35

25

?

(A) 50

(B) 55

(C) 60

(D) 45

Question 14: Difference is Cube of Position (+1³, +2³, +3³...)

3

4

12

39

?

(A) 88

(B) 95

(C) 100

(D) 103

Question 15: Compound Multiplication (×1, ×1.5, ×2, ×2.5...)

4

4

6

12

30

?

(A) 90

(B) 75

(C) 80

(D) 105

Question 16: Consecutive Twin Primes Difference (+2, +4, +2, +4...)

3

5

11

13

17

19

?

(A) 23

(B) 25

(C) 29

(D) 31

Question 17: Multiplicative Power Progression (nⁿ)

1

4

27

256

?

(A) 1024

(B) 3125

(C) 625

(D) 500

Question 18: Alternating Subtract and Divide (-3, ÷3, -3, ÷3...)

81

78

26

23

?

(A) 20

(B) 7.33

(C) 8

(D) 7.66

Question 19: Consecutive Composite Numbers Difference

2

6

12

20

29

?

(A) 38

(B) 39

(C) 40

(D) 41

Question 20: Triangular Power Rule [n × (n + 1) / 2 + n²]

2

7

15

26

?

(A) 36

(B) 38

(C) 40

(D) 42

2