Letter Shift
Shift each letter forward/backward by a fixed rate.
Logical Reasoning
Identify patterns, alphabetical shifts, mirror representations, and symbol/digit mappings to encode and decode messages quickly.
Coding-decoding asks you to infer the rule that maps a word (or symbol set) to its code, then apply it to a new input. Rules are usually letter shifts (fixed or increasing), reverse alphabets, position sums, mirror pairs, or digit encodings — sometimes combined with signs or numbers. Write the alphabet positions (A=1 … Z=26) on paper, compute the pattern explicitly, and test your rule against the given example before applying it.
Letters A-Z can be represented by positions (1-26) or their mirror values (sum = 27).
Shift each letter forward/backward by a fixed rate.
Replace A with Z, B with Y, etc. Formula: Pos + Mirror = 27.
The recurring question patterns in this topic — know the shape of each pattern before you solve.
Every letter moves by the same step (forward or backward).
CAT → DBU applies +1 to each letter.
Each successive letter shifts by a growing step.
FRIEND → HUMJTK uses +2, +3, +4, +5, +6, +7.
Letters map to their A↔Z mirror (M ↔ N, G ↔ T).
GOLD → TLWO is the mirror mapping; SILVER → HROEVI.
Letters become their alphabet positions, sums or differences.
DESK → 6-10-24-22 encodes by positions of a shifted form.
Decode words from a small phrase-to-code dictionary using common terms.
"walk" appears in two coded phrases with a shared token.
High-signal questions with full solution flow across difficulty patterns.
Classic exam problems worth internalizing — each one ships a complete step-by-step solution.
E=5, J=10, O=15, T=20, Y=25. Helps pinpoint letter positions instantly.
Where most students lose marks — review these before you sit the test.
You have mastered the theory. Now put it under pressure with a focused topic test and instant explanations.
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