Coding-Decoding - Message and Pattern Deciphering

Coding-Decoding questions test your ability to find patterns in coded messages and decode them.

Types of Coding

Letter Coding

• Direct Letter Coding: A→Z, B→Y, C→X (reverse order)
• Position Based: A→1, B→2, C→3 (numerical position)
• Skip Pattern: A→C, B→D, C→E (skip 1 letter)
• Opposite Letters: A↔Z, B↔Y, C↔X

Number Coding

• Letter Position: CAT = 3 + 1 + 20 = 24
• Multiplication: BAT = 2×1×20 = 40
• Digit Sum: 123 = 1+2+3 = 6

Substitution Coding

• Symbol Substitution: @ for A, # for N, etc.
• Word Substitution: Bird = Parrot, Animal = Dog

Mixed Coding

• Combination: Letters + Numbers + Symbols
• Mathematical Operations: Based on +, -, ×, ÷

Common Patterns

Direct Letter Codes

• Reverse Order: A=Z, B=Y, C=X
• Next Letter: A=B, B=C, C=D
• Skip Letters: A=C, B=D, C=E
• Previous Letter: A=Z, B=A, C=B

Number Codes

• Alphabet Position: A=1, B=2, C=3
• Reverse Position: A=26, B=25, C=24
• Digit Operations: Sum, product, difference

Practice Questions

Question 1

If TAP is coded as SZO, then how is MAP coded?

Question 2

In a certain code, COMPUTER is written as RFUVQNPC. How is MEDICINE written?

Question 3

If 123 = 6, 234 = 9, 345 = 12, then 456 = ?

Question 4

If A=1, B=2, C=3, what is the value of the word ‘CAT’?

Question 5

In the code language, ‘PENCIL’ is written as ‘RCPGNN’. How is ‘ERASER’ written?

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