Letter Series
Logic & Patterns: Letter Series
Letter Series
Letter Series
What you'll learn
- Use the alphabet order (A to Z) to find missing letters.
- Spot patterns that skip one or more letters.
- Work with letters moving forward or backward.
- Find letters using their position from the end of the alphabet.
Key concepts
Level 1 — Simple next letter
If the pattern moves one step at a time (A, B, C, D...), the next letter is simply the next one in the alphabet.
Level 2 — Skip patterns
Some patterns skip a fixed number of letters each time, like A, C, E, G (skipping one letter).
Level 3 — Backward patterns
Letters can also move backward, like Z, X, V (skipping one letter going down).
Level 4 — Position from the end
Z is the 1st letter from the end, Y is the 2nd, and so on. This helps solve trickier position puzzles.
NCERT anchor: CBSE Class 4 logical reasoning; English 4 alphabet order and sequencing skills
Worked example
Find the next letter: A, C, E, G, ?
Step 1 — Each letter skips one letter (step of 2).
Step 2 — After G, skip H, land on I.
Answer: **I**
Which letter is the 3rd letter from the end of the alphabet?
Step 1 — Z is 1st from the end, Y is 2nd, X is 3rd.
Answer: **X**
Common mistakes
| Mistake | Why it happens | Fix |
|---|---|---|
| Counting the skipped letter | Forgetting to skip it | Count carefully: A to C skips B |
| Going the wrong direction | Not checking if the series goes forward or backward | Compare the first two letters to see the direction |
| Miscounting from the end | Starting count from A instead of Z | Remember Z = 1st from the end |
| Losing track of position | Not writing down each letter's place number | Number each letter (A=1, B=2, ...) on scratch paper |
Quick check
- B, D, F, H, ? — what is next?
- Z, Y, X, W, ? — what is next?
- What is the 5th letter from the end of the alphabet?
- Stretch: In the pattern A, B, D, G, ?, the gap grows each time (+1, +2, +3...). What comes next?
Revision tip: Write out A to Z on scratch paper and number each letter — it makes skip and position patterns much easier to see.
Open the Practice tab for graded questions on Letter Series.
Key Takeaways (TL;DR)
- What you'll learn
- Key concepts
- Worked example
- Common mistakes
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