General Reasoning : Coding decoding & Blood relations Notes

By Deepanshu Rastogi|Updated : August 25th, 2021


CODING-DECODING: Coding-Decoding is one of the important topics of Reasoning. Coding is a method of transmission of signals or messages between sender and receiver, it is done confidentially, specially for security reasons so that the third person cannot understand, comprehend or decoded the sent message. The coded message can be decoded or decrypted by the receiver as he knows the pattern or method as how to interpret the message.

Now the question arises that, "why a student needs to study the chapter Coding-Decoding?". So, the answer for this question is: Coding-Decoding is taught to the students to check or test their abilities to decrypted the pattern which is applied on coded message, break the code and come out with the real message.

Importance of Coding-Decoding:

It is used in:

  • Alphabet Analogy
  • Alphabet Classification
  • Alphabet Series

Types of Coding-Decoding:

  • Word Coding-Decoding: In word coding-decoding, the original alphabets of word are replaced by certain different alphabets according to some specific rule.

Example: If RACE is coded as XGIK, then how HAIR will be Coded. In above example, each letter of the word XGIK is 6 letters ahead of the letters of word RACE, so the code for HAIR will be NGOX.

  • Number Coding-Decoding: In number coding-decoding, alphabets are replaced by according to their place values, it may be Direct Place Value or Reverse Place Value. For example, ‘A’ has a direct place value ‘1’ and reverse place value ‘26’.

Example: MNOP is coded as 4567.

In this example, Place value of M is 13.

Now, M ® 13 ®1+3 ® 4

Similarly, P ® 16 ® 1 + 6 ® 7

  • Symbol Coding-Decoding: In symbol coding-decoding, analysis is done according to the given word. The letters or alphabets of the given word are replaced by certain symbols like β, ©, π, % etc.

Example: In a certain language if WAVE is coded as 5%3β and WINS is coded as 59@©, then how SANE will be coded in that language. In above example, as we considered both the given words we found that code for S is ©, for A is %, for N is @ and for E is β. Therefore, the code for the word SANE is ©%@β.


BLOOD RELATION: Problems on Blood Relation involve analysis of certain blood relations. In these types of problem, you should give proper attention to find out the correct relation.

Some of the blood relations which is generally used in the question are given below in the tabular form: 

Mother’s or father’s son


Mother’s or father’s daughter


Father’s brother


Father’s sister


Father’s Father


Father’s mother


Mother’s brother

Maternal Uncle

Mother’s Sister

Maternal Aunt

Son’s wife

Daughter in law 

Daughter’s Husband


Husband’s or wife’s brother


Husband’s or wife’s sister


Brother’s son


Brother’s daughter


Sister’s husband

Brother in law 

Brother’s wife

Sister in law Great Grand Daughter

Grandson’s daughter

Great Grand Daughter 

Granddaughter’s daughter

Great Grand Daughter 

Mother’s father

Maternal Grand Father

Mother’s Mother

Maternal Grand Mother


  • If in a question if is not mention about paternal or maternal. By default, we consider the paternal type.
  • We cannot determine the gender of a person by name.
  • Male are represented by (square) or + (plus) sign and female are represented by (cycle) or 0 (minus) sign.



Example 1.

Pointing to a lady in the photograph, Shalu said, “Her son’s father is the son–in–law of my mother.” How is Shalu related to the lady?

Solution: Lady’s son’s father is the lady’s husband. So, the lady’s husband is the son–in–law of Shalu mother, i.e. the lady is the daughter of Shalu mother. Thus, Shalu is the lady’s sister.

Example 2.

A is the father of C and D is the son B. E is the brother of A. If C sister of D, how is B related to E?

Solution: For these types of question, we can use a generation tree.

So, B is a sister in the law of E.

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