Mastering Coding and Decoding: A Complete Guide

Mastering Coding and Decoding: A Complete Guide

Mastering Coding and Decoding: A Complete Guide

Introduction to Coding and Decoding

A code is essentially a system of signals or symbols used to transmit messages in a way that ensures confidentiality between the sender and receiver. Coding and decoding tests evaluate a person’s ability to interpret these signals by deciphering the coded message or creating a code for a given word or sentence.

This guide will break down various types of coding and decoding problems, provide examples, and suggest strategies to tackle them with ease.


Codes Based on the English Alphabet

When dealing with alphabet-based codes, the following numerical table is useful:

AlphabetPositionAlphabetPositionAlphabetPosition
A1J10S19
B2K11T20
C3L12U21
D4M13V22
E5N14W23
F6O15X24
G7P16Y25
H8Q17Z26
I9R18  

Types of Coding and Decoding Questions

1. Letter Coding

Case 1: Forming a Code for a Word (Coding)

Example:

  • Question: In a certain code, TEACHER is written as VGCEJGT. How is CHILDREN written in the same code?
    • Solution: Each letter in TEACHER is moved two steps forward:
      • T → V, E → G, A → C, and so on.
      • Similarly, CHILDREN becomes EJKNFTGP.

Case 2: Decoding a Given Code

Example:

  • Question: In a certain code, ROAD is written as WTFI. What does GJFY decode to?
    • Solution: Each letter is five steps behind its corresponding coded letter:
      • R → W (R + 5), O → T, A → F, D → I.
      • Following the same logic, BEAT is coded as GJFY.

2. Substitution

In substitution coding, words are replaced with other words.

Example:

  • Question: If ‘sky’ is called ‘star,’ ‘star’ is called ‘cloud,’ and ‘cloud’ is called ‘earth,’ where do birds fly?
    • Solution: Birds fly in the sky. Since ‘sky’ is coded as ‘star,’ the answer is star.

3. Deciphering Message Word Codes

Example:

  • Question: In a certain language:

    • ‘sun shines brightly’ is written as ‘ba lo sul.’

    • ‘houses are brightly lit’ is written as ‘kado ula ari ba.’

    • ‘light comes from sun’ is written as ‘dopi kup lo nro.’

    What is the code for ‘sun’ and ‘brightly’?

    • Solution:
      • Common word: ‘sun’ appears in the first and third sentences.
      • Common code: ‘lo’ is the code for ‘sun.’
      • Common word: ‘brightly’ appears in the first and second sentences.
      • Common code: ‘ba’ is the code for ‘brightly.’

Answer: lo (sun) and ba (brightly).


4. Numerical Code Values Assigned to Words

Example:

  • Question: If ROSE is coded as 6821, CHAIR as 73456, and PREACH as 961473, what is the code for SEARCH?
    • Solution: Assign numbers based on their position in the examples:
      • S → 2, E → 1, A → 4, R → 6, C → 7, H → 3.
      • SEARCH → 214673.

5. Analogy-Based Problems

Analogy questions involve identifying relationships between words, letters, or numbers.

Example 1:

  • Question: 42 : 20 :: 64 : ?
    • Solution: Relation is (2x + 2) : x.
      • 42 → 20 follows this relationship.
      • 64 → 31.

Example 2:

  • Question: WHISPER : SPEAK :: BRUSH : ?
    • Solution: To whisper means to speak softly. Similarly, to brush means to touch lightly.
    • Answer: TOUCH.

Conclusion

Mastering coding and decoding questions requires familiarity with various types of problems and consistent practice. Utilize the strategies and examples outlined in this guide to improve your speed and accuracy. Incorporate the suggested visuals, such as flowcharts, tables, and diagrams, to better understand and retain the concepts.

Mastering Coding and Decoding: A Complete Guide