Number Series – Part 3 | Find the Missing Number: 20 General Intelligence Questions

 Welcome to Part 3 of our Number Series practice series! This set features 20 new missing-number questions designed to test your numerical reasoning, logical thinking, and pattern-recognition skills.

Analyze each number series carefully, identify the hidden pattern, and determine the missing number. The questions are designed to provide a good mix of patterns and progressively challenge your problem-solving ability.

This practice set is useful for General Intelligence, Mental Ability, Olympiad, scholarship, and competitive exam preparation.

Look carefully, find the pattern, and see how many of the 20 questions you can solve!

Number Series Mastery: Set 3

Challenge yourself with 20 newly designed logical ideas including sum of digits addition, Lucas numbers, prime differences, fractional decay, and interleaved polynomial growth!

Question 1: Digital Root Addition (+ Sum of Digits)

19

29

40

44

?

(A) 48

(B) 52

(C) 56

(D) 50

Question 2: Lucas Sequence (2, 1, 3, 4, 7...)

2

1

3

4

7

11

?

(A) 15

(B) 16

(C) 18

(D) 21

Question 3: Consecutive Prime Additions (+2, +3, +5, +7...)

10

12

15

20

27

?

(A) 34

(B) 36

(C) 37

(D) 38

Question 4: Polynomial Progression (n³ + n²)

2

12

36

80

150

?

(A) 252

(B) 240

(C) 264

(D) 222

Question 5: Halving with Constant Shift (÷2 + 3)

100

53

29.5

17.75

?

(A) 10.375

(B) 11.25

(C) 11.875

(D) 12.125

Question 6: Subtracting Squares of Position (-1², -2², -3²...)

100

99

95

86

70

?

(A) 41

(B) 45

(C) 49

(D) 54

Question 7: Product of Previous Two Terms Plus One (Tₙ = Tₙ₋₁ × Tₙ₋₂ + 1)

1

2

3

7

22

?

(A) 144

(B) 150

(C) 154

(D) 155

Question 8: Interleaved Multiplication and Addition (×2, +3, ×2, +3...)

4

8

11

22

25

?

(A) 50

(B) 28

(C) 53

(D) 48

Question 9: Doubling Differences Pattern (+2, +4, +8, +16...)

3

5

9

17

33

?

(A) 61

(B) 63

(C) 65

(D) 67

Question 10: Pentagonal Numbers [n(3n - 1) / 2]

1

5

12

22

35

?

(A) 48

(B) 51

(C) 52

(D) 55

Question 11: Base 10 Digit Repetition Count (Look-and-Say Idea)

1

11

21

1211

?

(A) 112211

(B) 312211

(C) 211211

(D) 111221

Question 12: Alternating Cubic Difference (+1³, -2³, +3³, -4³...)

50

51

43

70

?

(A) 6

(B) 10

(C) 12

(D) 134

Question 13: Factorial Fraction Reduction (n! / 2ⁿ)

0.5

0.5

0.75

1.5

3.75

?

(A) 9.5

(B) 10.75

(C) 11.25

(D) 12.50

Question 14: Difference of Primes Sequence (pₙ₊₁ - pₙ)

1

2

2

4

2

4

?

(A) 1

(B) 2

(C) 3

(D) 6

Question 15: Triple Step Recurrence (Tₙ = 2Tₙ₋₁ - 1)

2

3

5

9

17

?

(A) 25

(B) 29

(C) 31

(D) 33

Question 16: Interleaved Squares and Cubes

1

1

4

8

9

27

?

(A) 16

(B) 64

(C) 36

(D) 25

Question 17: Digit Reversing and Incremental Sum

14

41

45

54

58

?

(A) 62

(B) 85

(C) 82

(D) 68

Question 18: Consecutive Primes Plus Position (pₙ + n)

3

5

8

11

16

?

(A) 17

(B) 18

(C) 19

(D) 21

Question 19: Geometric Decay with Increasing Step Subtraction

120

60

20

5

?

(A) 1

(B) 0

(C) 2

(D) 0.5

Question 20: Triangular Numbers Plus Constant (Tₙ + 5)

6

8

11

15

20

?

(A) 24

(B) 25

(C) 27

(D) 26

2