Coding and decoding reasoning questions part #1-fully explained

Part 1: These questions are asked in most of the competitive exams in all over the world. The coding and decoding of reasoning test is set up to judge the candidate’s ability to decipher the rule that codes a word/message and break the code to decipher the message. In questions, a word is given coded in a particular way and candidates are asked to code the other given word in the same manner as the first given word was coded.

There are basically five types of coding and decoding questions that are asked in the examination.

1. Order based questions

2. Substitution for words

3. Number symbol coding

4. Substitution based coding

5. Deciphering number and symbol codes in a message

1. Order based questions:-

Here is a question for example of this type of questions.

Ex. In a certain language, if ‘BOYS’ is written as ‘SOYB’, how is ‘GIRL’ coded in that language.

Solution:- in these types of questions, the order of placement of alphabets or words usually changes. Now in this question, letter B has been placed at 4th position and the positions of 2nd and third letters are not changed. Letters at 4th position has been placed at first position in the coded language.

B-1st position–>S-4th position



S-4th position–>B-1st position



G-1st position–>L-4th position



L-4th position–>G-1st position


2. Substitution for words

In this type of question, a particular word is assigned a certain substituted name and a question is asked to be given in that substituted name. here is an example…

Ex. if sky is star, star is cloud, cloud is earth, earth is tree and tree is book, then where do the birds fly?

1. Star

2. Sky

3. Cloud

4. Earth

5. None of these

Solution:- we know that in reality birds fly in the sky but in this question, as given sky is called star (option no. 1). So star (option no. 1) is the answer.

Learn Coding & Decoding Part 1

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