Letter and Symbol Series questions with answers and concepts

Learn letter and symbol series with concept notes and worked examples, then practise focused questions with explained answers. Build accuracy for placement and competitive aptitude tests before trying timed mode.

114 practice questionsPage updated 11 Nov 2026Review metadata pendingPractice questions

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Letter series problems involve identifying patterns in sequences of alphabets. These questions test your ability to recognise alphabetical positions, skip patterns, reverse sequences, and alternating arrangements to find the missing term or next letter in a series.

Key concepts

Alphabetical Position Values

Each letter corresponds to a numerical position: $A = 1$ , $B = 2$ , $C = 3$ , ..., $Z = 26$ . For reverse position (Z to A): $Z = 1$ , $Y = 2$ , $X = 3$ , ..., $A = 26$ . Common patterns include adding/subtracting fixed values, multiplying positions, or using squares and primes. Memorising $A = 1$ , $E = 5$ , $I = 9$ , $O = 15$ , $U = 21$ , and $M = 13$ (middle) helps quick calculations.

Skip Series Patterns

Letters may skip a fixed number of positions: AB, DE, GH (skip 2), or AC, EG, IK (skip increasing). Check if the gap between consecutive letters is constant or follows its own pattern (increasing by 1, 2, etc.). Multi-level skips occur when the skip amount itself changes: +1, +2, +3, +4 pattern.

Reverse Alphabet Series

Series may progress backwards: Z, Y, X... or mix forward and backward movements. For ZYXW (reverse consecutive) or ZXV (skip in reverse). Watch for patterns that switch direction at certain points: A, B, C, Z, Y (forward then reverse). Calculate positions from $Z = 1$ for clarity.

Alternate Series

Two interleaved series: positions 1,3,5,7 form one pattern; positions 2,4,6,8 form another. Example: A_C_E_G (odd positions: +2) and _B_D_F_H (even positions: +2). Separate the series mentally to identify each pattern independently before combining.

Letter Group Patterns

Groups of letters follow rules: ABC, CDE, EFG (each group starts +2 from previous); or AB, BC, CD, DE (consecutive pairs). Within groups, check for internal patterns like vowel placement, consonant clusters, or symmetrical positions (A-Z, B-Y, C-X mirror pairs).

Complex Pattern Recognition

Advanced series combine multiple rules: position arithmetic, vowel/consonant alternation, or word fragments. Example: ACE, GIK, MOQ (skip 1 letter, start +6). Look for prime numbers, Fibonacci, squares, or cubes in position values. When stuck, write positions numerically to reveal hidden mathematical relationships.

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Worked examples

Example 1

Find the next letter in the series: A, E, I, M, ?

Solution

Step 1: Convert letters to positions - A=1, $E = 5$ , $I = 9$ , $M = 13$ .
Step 2: Identify the pattern - differences are $5 - 1 = 4$ , $9 - 5 = 4$ , $13 - 9 = 4$ .
Step 3: The pattern adds 4 to each position.
Step 4: Next position = 13 + 4 = 17.
Step 5: Position 17 corresponds to letter Q.
Answer: Q

Example 2

Complete the series: B, D, G, K, ?

Solution

Step 1: Convert to positions - B=2, $D = 4$ , $G = 7$ , $K = 11$ .
Step 2: Find differences - 4-2=2, $7 - 4 = 3$ , $11 - 7 = 4$ .
Step 3: The skip increases by 1 each time: +2, +3, +4, so next is +5.
Step 4: Next position = 11 + 5 = 16.
Step 5: Position 16 corresponds to letter P.
Answer: P

Example 3

Find the missing letters: AZ, BY, CX, DW, ?

Solution

Step 1: Analyse first letters of each pair: $A = 1$ , $B = 2$ , $C = 3$ , $D = 4$ . Pattern: +1.
Step 2: Next first letter position = 4 + 1 = 5, which is E.
Step 3: Analyse second letters: Z=26(reverse:1), Y=25(reverse:2), X=24(reverse:3), W=23(reverse:4).
Step 4: Pattern: second letters decrease by 1 position from Z. Next is V=22(reverse:5).
Step 5: Combine: first letter E, second letter V.
Answer: EV

Example 4

What comes next: A, Z, B, Y, C, X, ?

Solution

Step 1: This is an alternate series with two patterns interleaved.
Step 2: Odd positions (1,3,5,7): $A = 1$ , $B = 2$ , $C = 3$ . Pattern: consecutive letters.
Step 3: Position 7 should be $D = 4$ .
Step 4: Even positions (2,4,6): $Z = 26$ , $Y = 25$ , $X = 24$ . Pattern: reverse consecutive.
Step 5: Position 8 should be $W = 23$ .
Step 6: The 7th letter is asked, which follows C at position 5.
Answer: D

Representative solved questions

See the kind of question in this topic before opening the full practice set.

Question 1

Find the next term: A, C, F, J, O, ?

Answer: C. U

Explanation

Step 1: The jumps are +2, +3, +4, +5.
Step 2: So the next jump should be +6.
Step 3: $O (15) + 6 = U (21)$ .
Answer: U

Sources and review notes

This is an AISEA-authored practice question.

Review status: accepted · Reviewed 2026-08-13 · structure and answer-key checks, editorial quality checks, duplicate screening

Question 2

Find the next term: B, D, G, K, P, ?

Answer: B. V

Explanation

Step 1: The jumps are +2, +3, +4, +5.
Step 2: Next jump is +6.
Step 3: $P (16) + 6 = V (22)$ .
Answer: V

Sources and review notes

This is an AISEA-authored practice question.

Review status: accepted · Reviewed 2026-08-13 · structure and answer-key checks, editorial quality checks, duplicate screening

Question 3

Find the next term: A, B, D, G, K, ?

Answer: B. P

Explanation

Step 1: The position increases are +1, +2, +3, +4.
Step 2: Next increase should be +5.
Step 3: $K (11) + 5 = P (16)$ .
Answer: P

Sources and review notes

This is an AISEA-authored practice question.

Review status: accepted · Reviewed 2026-08-13 · structure and answer-key checks, editorial quality checks, duplicate screening

Common mistakes and useful habits

Always write down alphabetical positions (A=1 to Z=26) when analysing a series - numerical patterns are easier to spot than letters.
For complex series, try separating into odd and even positions to detect if two alternating patterns exist.
Memorise key positions: A=1, E=5, I=9, O=15, U=21, M=13 (middle), Z=26 for quick calculations without counting.
When letters decrease in a series, work from Z backwards (Z=1, Y=2...) or subtract from 27 to get reverse positions.
If stuck, check for prime number positions, Fibonacci sequence, or square numbers (1,4,9,16,25) as these are common in competitive exams.
For mirror pairs (A-Z, B-Y, C-X), remember that the sum of positions equals 27 (A+Z=1+26=27, B+Y=2+25=27).

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Next topic: Analogies

Letter and Symbol Series questions with answers and concepts

114 practice questionsPage updated 11 Nov 2026Review metadata pendingPractice questions

Practise this concept

Key concepts

Alphabetical Position Values

Skip Series Patterns

Reverse Alphabet Series

Alternate Series

Letter Group Patterns

Complex Pattern Recognition

Check the idea while it is fresh.Open a focused exercise without losing this article.Practise this concept

Worked examples

Example 1

Find the next letter in the series: A, E, I, M, ?

Solution

Example 2

Complete the series: B, D, G, K, ?

Solution

Example 3

Find the missing letters: AZ, BY, CX, DW, ?

Solution

Example 4

What comes next: A, Z, B, Y, C, X, ?

Solution

Representative solved questions

See the kind of question in this topic before opening the full practice set.

Question 1

Find the next term: A, C, F, J, O, ?

Answer: C. U

Explanation

Step 1: The jumps are +2, +3, +4, +5.
Step 2: So the next jump should be +6.
Step 3: $O (15) + 6 = U (21)$ .
Answer: U

Sources and review notes

This is an AISEA-authored practice question.

Review status: accepted · Reviewed 2026-08-13 · structure and answer-key checks, editorial quality checks, duplicate screening

Question 2

Find the next term: B, D, G, K, P, ?

Answer: B. V

Explanation

Step 1: The jumps are +2, +3, +4, +5.
Step 2: Next jump is +6.
Step 3: $P (16) + 6 = V (22)$ .
Answer: V

Sources and review notes

This is an AISEA-authored practice question.

Review status: accepted · Reviewed 2026-08-13 · structure and answer-key checks, editorial quality checks, duplicate screening

Question 3

Find the next term: A, B, D, G, K, ?

Answer: B. P

Explanation

Step 1: The position increases are +1, +2, +3, +4.
Step 2: Next increase should be +5.
Step 3: $K (11) + 5 = P (16)$ .
Answer: P

Sources and review notes

This is an AISEA-authored practice question.

Review status: accepted · Reviewed 2026-08-13 · structure and answer-key checks, editorial quality checks, duplicate screening

Common mistakes and useful habits

Always write down alphabetical positions (A=1 to Z=26) when analysing a series - numerical patterns are easier to spot than letters.
For complex series, try separating into odd and even positions to detect if two alternating patterns exist.
Memorise key positions: A=1, E=5, I=9, O=15, U=21, M=13 (middle), Z=26 for quick calculations without counting.
When letters decrease in a series, work from Z backwards (Z=1, Y=2...) or subtract from 27 to get reverse positions.
If stuck, check for prime number positions, Fibonacci sequence, or square numbers (1,4,9,16,25) as these are common in competitive exams.
For mirror pairs (A-Z, B-Y, C-X), remember that the sum of positions equals 27 (A+Z=1+26=27, B+Y=2+25=27).

Ready to test your understanding?

Work through 114 questions with explanations after each answer.

Start practice

Next topic: Analogies

Key concepts

Alphabetical Position Values

Skip Series Patterns

Reverse Alphabet Series

Alternate Series

Letter Group Patterns

Complex Pattern Recognition

Worked examples

Example 1

Solution

Example 2

Solution

Example 3

Solution

Example 4

Solution

Representative solved questions

Question 1

Question 2

Question 3

Common mistakes and useful habits

Ready to test your understanding?

Keep building the same skill family.

Key concepts

Alphabetical Position Values

Skip Series Patterns

Reverse Alphabet Series

Alternate Series

Letter Group Patterns

Complex Pattern Recognition

Worked examples

Example 1

Solution

Example 2

Solution

Example 3

Solution

Example 4

Solution

Representative solved questions

Question 1

Question 2

Question 3

Common mistakes and useful habits

Ready to test your understanding?

Keep building the same skill family.