Home / Verbal & Reasoning / Series

25 Series Questions and Answers

25 solved Series questions with step-by-step explanations. Includes formulas, shortcuts, and tips for placement tests and competitive exams.

Play Timed Quiz View Tutorial

Advanced series questions for experienced learners. These medium-to-hard questions test deeper understanding and are ideal for those who have already mastered the basics. Each question includes a detailed explanation.

Q1 Medium

Identify the odd term in the series: 5, 11, 15, 20, 25

  • A. 5
  • B. 25
  • C. 11 ✓
  • D. 10
Explanation: For number series, first find the difference between consecutive terms. If the differences form a pattern, that reveals the rule. Check for arithmetic, geometric, or square/cube patterns. Series should increase by 5. '11' breaks the pattern.
Q2 Medium

What should come next in this AP? 7, 13, 19, 25, 31, ?

  • A. 37 ✓
  • B. 35
  • C. 39
  • D. 33
Explanation: Common difference is 6. Next = 37.
Q3 Medium

Find the next number: 8, 13, 18, 23, 28, ?

  • A. 33 ✓
  • B. 29
  • C. 31
  • D. 35
Explanation: Common difference is 5. Next = 33.
Q4 Medium

Identify the odd term in the series: 7, 11, 13, 16, 19

  • A. 11 ✓
  • B. 7
  • C. 19
  • D. 10
Explanation: For number series, first find the difference between consecutive terms. If the differences form a pattern, that reveals the rule. Check for arithmetic, geometric, or square/cube patterns. Series should increase by 3. '11' breaks the pattern.
Q5 Medium

Find the next letter in the series: G, H, I, J, K, ?

  • A. N
  • B. K
  • C. M
  • D. L ✓
Explanation: For number series, first find the difference between consecutive terms. If the differences form a pattern, that reveals the rule. Check for arithmetic, geometric, or square/cube patterns. Letters progress by +1 position each step. So next is L.
Q6 Medium

Identify the odd term in the series: 3, 10, 13, 18, 23

  • A. 10 ✓
  • B. 23
  • C. 8
  • D. 3
Explanation: For number series, first find the difference between consecutive terms. If the differences form a pattern, that reveals the rule. Check for arithmetic, geometric, or square/cube patterns. Series should increase by 5. '10' breaks the pattern.
Q7 Medium

Find the next number: 1, 5, 10, 16, 23, ?

  • A. 28
  • B. 32
  • C. 30
  • D. 31 ✓
Explanation: Differences increase by 1 each time starting from +4. Next value is 31.
Q8 Medium

Identify the odd term in the series: 9, 11, 16, 15, 17

  • A. 16 ✓
  • B. 17
  • C. 9
  • D. 13
Explanation: For number series, first find the difference between consecutive terms. If the differences form a pattern, that reveals the rule. Check for arithmetic, geometric, or square/cube patterns. Series should increase by 2. '16' breaks the pattern.
Q9 Medium

Complete the geometric series: 2, 6, 18, 54, 162, ?

  • A. 483
  • B. 486 ✓
  • C. 480
  • D. 489
Explanation: For number series, first find the difference between consecutive terms. If the differences form a pattern, that reveals the rule. Check for arithmetic, geometric, or square/cube patterns. Each term is multiplied by 3. Next term is 486.
Q10 Medium

Identify the odd term in the series: 8, 10, 12, 15, 16

  • A. 16
  • B. 15 ✓
  • C. 8
  • D. 14
Explanation: For number series, first find the difference between consecutive terms. If the differences form a pattern, that reveals the rule. Check for arithmetic, geometric, or square/cube patterns. Series should increase by 2. '15' breaks the pattern.
Q11 Medium

Identify the next term: 1, 4, 8, 13, 19, ?

  • A. 25
  • B. 27
  • C. 23
  • D. 26 ✓
Explanation: Differences increase by 1 each time starting from +3. Next value is 26.
Q12 Medium

Complete the alphabet pattern: E, G, I, K, M, ?

  • A. O ✓
  • B. N
  • C. P
  • D. Q
Explanation: Letters progress by +2 position each step. So next is O.
Q13 Medium

Find the next letter in the series: F, I, L, O, R, ?

  • A. W
  • B. T
  • C. V
  • D. U ✓
Explanation: For number series, first find the difference between consecutive terms. If the differences form a pattern, that reveals the rule. Check for arithmetic, geometric, or square/cube patterns. Letters progress by +3 position each step. So next is U.
Q14 Medium

Complete the arithmetic series: 6, 10, 14, 18, 22, ?

  • A. 22
  • B. 24
  • C. 26 ✓
  • D. 28
Explanation: For number series, first find the difference between consecutive terms. If the differences form a pattern, that reveals the rule. Check for arithmetic, geometric, or square/cube patterns. Common difference is 4. Next = 26.
Q15 Medium

Complete this progressive pattern: 1, 5, 10, 16, 23, ?

  • A. 31 ✓
  • B. 32
  • C. 28
  • D. 30
Explanation: Differences increase by 1 each time starting from +4. Next value is 31.
Q16 Medium

Find the next number: 2, 4, 6, 8, 10, ?

  • A. 10
  • B. 8
  • C. 14
  • D. 12 ✓
Explanation: Common difference is 2. Next = 12.
Q17 Medium

What is the next term in GP 2, 6, 18, 54, 162, ?

  • A. 483
  • B. 486 ✓
  • C. 489
  • D. 480
Explanation: Each term is multiplied by 3. Next term is 486.
Q18 Medium

Find the next letter in the series: C, D, E, F, G, ?

  • A. I
  • B. H ✓
  • C. G
  • D. J
Explanation: For number series, first find the difference between consecutive terms. If the differences form a pattern, that reveals the rule. Check for arithmetic, geometric, or square/cube patterns. Letters progress by +1 position each step. So next is H.
Q19 Medium

Identify the odd term in the series: 10, 15, 23, 25, 30

  • A. 30
  • B. 20
  • C. 23 ✓
  • D. 10
Explanation: For number series, first find the difference between consecutive terms. If the differences form a pattern, that reveals the rule. Check for arithmetic, geometric, or square/cube patterns. Series should increase by 5. '23' breaks the pattern.
Q20 Medium

Find the next letter in the series: C, F, I, L, O, ?

  • A. S
  • B. T
  • C. Q
  • D. R ✓
Explanation: For number series, first find the difference between consecutive terms. If the differences form a pattern, that reveals the rule. Check for arithmetic, geometric, or square/cube patterns. Letters progress by +3 position each step. So next is R.
Q21 Medium

Find the next number: 6, 10, 14, 18, 22, ?

  • A. 22
  • B. 28
  • C. 24
  • D. 26 ✓
Explanation: Common difference is 4. Next = 26.
Q22 Medium

What is the next term in GP 4, 8, 16, 32, 64, ?

  • A. 122
  • B. 131
  • C. 125
  • D. 128 ✓
Explanation: Each term is multiplied by 2. Next term is 128.
Q23 Medium

Find the next number: 6, 11, 16, 21, 26, ?

  • A. 33
  • B. 29
  • C. 31 ✓
  • D. 27
Explanation: Common difference is 5. Next = 31.
Q24 Medium

Find the next term in the alternating series: 7, 17, 10, 20, 13, ?

  • A. 13 ✓
  • B. 11
  • C. 9
  • D. 15
Explanation: For number series, first find the difference between consecutive terms. If the differences form a pattern, that reveals the rule. Check for arithmetic, geometric, or square/cube patterns. Odd and even positions form two APs. Continue the odd-position sequence.
Q25 Medium

Which letter comes next? I, J, K, L, M, ?

  • A. O
  • B. M
  • C. P
  • D. N ✓
Explanation: Letters progress by +1 position each step. So next is N.

More Series Practice Resources

For more series practice, try our timed quiz mode that generates fresh questions every session.

Timed Quiz → Tutorial → Analogies Blood relations Coding decoding Direction sense Fill blanks Odd one out