40  Blood Relations

40.1 Introduction

Blood Relation questions test logical reasoning through family relationships. You must decode terms like father, mother, son, uncle, cousin, in-law, etc., and solve puzzles where relationships are hidden in coded statements or symbols.
They check clarity of thought, quick inference, and ability to track multiple connections.

40.2 1) Basic Relationships

40.2.1 1.1 Direct Terms

  • Father / Mother → Parents.
  • Son / Daughter → Children.
  • Brother / Sister → Siblings.
  • Grandfather / Grandmother → Parents of parents.
  • Grandson / Granddaughter → Children of children.

40.2.2 1.2 Extended Family

  • Uncle → Brother of father/mother.
  • Aunt → Sister of father/mother.
  • Nephew / Niece → Son/daughter of brother/sister.
  • Cousin → Child of uncle/aunt.

40.2.3 1.3 In-Laws

  • Father-in-law → Father of spouse.
  • Mother-in-law → Mother of spouse.
  • Brother-in-law → Brother of spouse or husband of sister.
  • Sister-in-law → Sister of spouse or wife of brother.

40.3 2) Types of Questions

40.3.1 2.1 Direct Statement

“X is the father of Y.” → Relationship straightforward.

40.3.2 2.2 Puzzles

Chain of statements where you must connect multiple relations.
Example: A is brother of B, B is daughter of C. What is A to C?
→ A is son of C.

40.3.3 2.3 Coded Relations

Symbols replace relations.
Example: “A # B” means A is father of B. “B * C” means B is sister of C. Decode relationship.

40.3.4 2.4 Mixed Blood Relations

Family tree questions where you must infer missing links from descriptions.

40.4 3) Solving Strategies

  1. Draw family tree → use vertical for generations, horizontal for siblings.
  2. Track gender carefully → some questions hide gender unless specified.
  3. Use elimination → multiple-choice can often be narrowed quickly.
  4. Watch for traps → “only son”, “only daughter”, “cousin vs brother”.

40.5 4) Solved Examples

40.5.1 Example 1

Pointing to a man, Rita said: “He is the son of my grandfather’s only son.” How is the man related to Rita?
- Grandfather’s only son = Rita’s father.
- Son of her father = brother.
Answer: Brother.

40.5.2 Example 2

A is the brother of B. C is the mother of B. D is the father of C. How is A related to D?
- A and B are siblings.
- C is their mother.
- D is their maternal grandfather.
Answer: Grandson.

40.5.3 Example 3

If A + B means A is the father of B, A − B means A is sister of B, A × B means A is brother of B, and A ÷ B means A is mother of B, then what does P − Q ÷ R mean?
- Q ÷ R → Q is mother of R.
- P − Q → P is sister of Q.
So P is maternal aunt of R.
Answer: Maternal Aunt.

40.5.4 Example 4

Introducing a man, a woman said: “He is the son of my mother’s brother.” How is the man related to her?
- Mother’s brother = maternal uncle.
- Uncle’s son = cousin.
Answer: Cousin.

40.6 5) Practice Questions

  1. Pointing to a man, Sita said: “He is the husband of my only daughter.” How is the man related to Sita?
  2. If A is brother of B and B is sister of C, how is A related to C?
  3. Pointing to a woman, a man said: “Her mother is the only daughter of my mother.” How is the woman related to the man?
  4. In a coded relation: P $ Q means P is the father of Q, and Q # R means Q is the sister of R. Then what does P $ Q # R mean?
  5. R is father of S. S is sister of T. How is T related to R?

40.7 6) Answer Key

  1. Son-in-law.
  2. Brother.
  3. Niece.
  4. P is the father of Q, and Q is the sister of R → P is the father of both Q and R.
  5. Son or Daughter (gender not specified).

40.8 Summary

  • Always note generation (parent, sibling, child, grandparent).
  • Track gender clues carefully.
  • Use family trees for puzzles.
  • For coded relations, decode each symbol step by step.
  • Practice improves speed in these common reasoning questions.