Coding-Decoding: All Types Explained with Tricks for Every Pattern

Coding-decoding carries 3-5 marks in every competitive exam. Master all types and you'll never lose marks here.

Type 1: Letter Shifting

Each letter is shifted by a fixed number. Example: CAT → FDW (each letter +3). Quick check: Compare first letters of original and code to find the shift.

Type 2: Reverse/Mirror Coding

A=Z, B=Y, C=X... (position sum = 27). BANK → YZMN. Shortcut: Subtract each letter's position from 27.

Type 3: Number Coding

Letters replaced by numbers based on some rule. Common rules: Position value (A=1, B=2), reverse position (A=26, B=25), or custom assignment given in the question.

Type 4: Condition-Based Coding (New Pattern)

Modern banking exams use this: Different conditions apply based on vowels/consonants, position, or surrounding letters. Read all conditions carefully. Apply them step by step. Don't try to do it mentally — write each step.