Reasoning Ability

Blood Relations questions with solutions

Blood relation questions appear in bank, SSC and railway reasoning sections, either as single questions, pointing-to-a-photograph puzzles, or coded relations (A + B means A is the mother of B).

Start practising Timed sectional drill →

Prepared by the CBTAdda content team · Updated 28 October 2026 · How we check our content

How to solve blood relations questions

Draw a family tree: generations one below another, + for male and − for female, a horizontal line for siblings and = for a married couple.
Start from the end of a long sentence (“my grandfather's only son”) and work backwards to the speaker.
Do not assume gender from a letter. Only names, he/she, and words like brother or daughter fix it.

Common trap: Questions with “only son” or “only daughter” are designed so that the person turns out to be the speaker or their parent.

10 practice questions

Tap an option to check it, or open “Show answer” for the full working.

A is the father of B. B is the sister of C. C is the son of D. How is D related to A?
Show answer
Answer: (A) Wife. A is the father of B and C, and C is the son of D. D is the other parent, so D is A's wife.
Pointing to a man, Neha said, “His only brother is the father of my daughter's father.” How is the man related to Neha?
Show answer
Answer: (B) Uncle of her husband. Her daughter's father is Neha's husband. His father is Neha's father-in-law, whose only brother is the man. So the man is her husband's uncle.
P is Q's brother. R is Q's mother. S is R's father. T is S's mother. How is P related to T?
Show answer
Answer: (B) Great-grandson. P is R's son, R is S's child and S is T's child. That is three generations below T, so P is T's great-grandson.
If X + Y means X is the mother of Y, X − Y means X is the brother of Y and X × Y means X is the father of Y, what does A + B − C × D mean?
Show answer
Answer: (A) A is the grandmother of D. A is the mother of B, B is the brother of C, so A is also C's mother. C is the father of D, so A is D's grandmother.
M is the son of N. N is the daughter of O. O is the wife of P. How is M related to P?
Show answer
Answer: (B) Grandson. N is the daughter of O and P (O is P's wife). M is N's son, so M is P's grandson.
A woman says, “My mother's only son's wife is my ___.”
Show answer
Answer: (B) Sister-in-law. Her mother's only son is her brother. Her brother's wife is her sister-in-law.
Rahul's mother is the only daughter of Mohan's father. How is Mohan related to Rahul?
Show answer
Answer: (C) Maternal uncle. The only daughter of Mohan's father is Mohan's sister, and she is Rahul's mother. So Mohan is Rahul's maternal uncle (mama).
X is the brother of Y. Y is the sister of Z. Z is the father of W. How is X related to W?
Show answer
Answer: (B) Uncle. X, Y and Z are siblings, and X is male. Z is W's father, so X is W's uncle.
Introducing Sunil, Kavita says, “He is the only son of my grandfather's only son.” How is Sunil related to Kavita?
Show answer
Answer: (B) Brother. Her grandfather's only son is Kavita's father. His only son is Kavita's brother.
A and B are brothers. C is the wife of A. D is the son of B. How is C related to D?
Show answer
Answer: (B) Aunt. D is B's son, so A is D's uncle. C is A's wife, so C is D's aunt.