1
Find the next number in the series: 8, 14, 20, 26, 32, ?
Correct answer: C. 38
The terms increase by 6 each time. The next term is 38.
easy
Number and Letter Series MCQs
Solved number series and letter series MCQs for SSC and banking reasoning: find the rule (add, multiply, squares, primes, alternating series) and the next term, with worked explanations.
20 MCQsUpdated 27 October 2026
This set covers number and letter series built on differences, squares and cubes, multiplication patterns and alternating rules.
Write the differences between terms first. If they don't form a pattern, try ratios, squares, cubes or alternate terms.
- 2
Find the next number in the series: 120, 111, 102, 93, 84, ?
Correct answer: B. 75
The terms decrease by 9 each time. The next term is 75.
easy - 3
Find the next number in the series: 5, 10, 20, 40, 80, ?
Correct answer: B. 160
Each term is double the previous one. The next term is 160.
easy - 4
Find the next number in the series: 2, 6, 18, 54, 162, ?
Correct answer: D. 486
Each term is three times the previous one. The next term is 486.
easy - 5
Find the next number in the series: 4, 7, 12, 19, 28, ?
Correct answer: D. 39
The terms are n² + 3 for n = 1, 2, 3, … (4, 7, 12, 19, 28). The next term is 39.
medium - 6
Find the next number in the series: 8, 27, 64, 125, ?
Correct answer: D. 216
The terms are cubes: 2³, 3³, 4³, 5³. The next term is 216.
medium - 7
Find the next number in the series: 2, 6, 12, 20, 30, ?
Correct answer: D. 42
The terms are n × (n + 1): 1×2, 2×3, 3×4, 4×5, 5×6. The next term is 42.
medium - 8
Find the next number in the series: 3, 5, 7, 11, 13, 17, ?
Correct answer: A. 19
The terms are consecutive prime numbers; 21 is not prime (3 × 7). The next term is 19.
easy - 9
Find the next number in the series: 3, 5, 9, 15, 23, 33, ?
Correct answer: C. 45
The differences are 2, 4, 6, 8, 10, so the next difference is 12. The next term is 45.
medium - 10
Find the next number in the series: 2, 3, 5, 8, 13, 21, ?
Correct answer: C. 34
Each term is the sum of the two terms before it (13 + 21 = 34). The next term is 34.
medium - 11
Find the next number in the series: 4, 9, 19, 39, 79, ?
Correct answer: A. 159
Each term is double the previous term plus 1. The next term is 159.
medium - 12
Find the next number in the series: 2, 4, 10, 28, 82, ?
Correct answer: A. 244
Each term is three times the previous term minus 2. The next term is 244.
hard - 13
Find the next number in the series: 1, 4, 8, 11, 22, 25, ?
Correct answer: D. 50
The rule alternates: add 3, then multiply by 2 (1 → 4 → 8 → 11 → 22 → 25 → 50). The next term is 50.
hard - 14
Find the next number in the series: 10, 50, 15, 46, 20, 42, 25, ?
Correct answer: D. 38
Two series alternate: 10, 15, 20, 25 (+5) and 50, 46, 42 (−4). The next term belongs to the second series: 42 − 4 = 38. The next term is 38.
Read detailshard - 15
Find the next number in the series: 512, 256, 128, 64, 32, ?
Correct answer: B. 16
Each term is half of the previous one. The next term is 16.
easy - 16
Find the missing number: 7, 14, ?, 56, 112
Correct answer: A. 28
Each term is double the previous one, so 14 × 2 = 28 (and 28 × 2 = 56).
easy - 17
Find the missing number: 1, 8, 27, ?, 125, 216
Correct answer: B. 64
The terms are cubes 1³, 2³, 3³, 4³, 5³, 6³, so the missing term is 4³ = 64.
easy - 18
What comes next: C, G, K, O, S, ?
Correct answer: A. W
Each letter moves 4 places forward in the alphabet: S + 4 = W.
medium - 19
What comes next: Z, W, T, Q, N, ?
Correct answer: D. K
Each letter moves 3 places back in the alphabet: N − 3 = K.
medium - 20
What comes next: AZ, BY, CX, DW, ?
Correct answer: B. EV
The first letter moves forward (A, B, C, D, E) and the second moves back from Z (Z, Y, X, W, V), so each pair is a letter and its opposite in the alphabet. The next pair is EV.
Read detailsmedium