Blood Relations

Why This Chapter Matters

Blood Relations has 3-5 marks in Banking exams. Questions involve 2-3 generations and require systematic diagramming. Coded blood relations have higher difficulty.

Core Concepts

1. Generation Chart

Draw family tree with clear labels:

•Horizontal lines = same generation, siblings

•Vertical lines = parent-child

•= (equals sign) = married couple

Standard representation:

Grandfather - Grandmother

Father - Mother (aunt/uncle on other side)

YOU (siblings at same level)

2. Relationship Terms

Ascending (elders): Father, Mother, Grandfather, Grandmother, Uncle, Aunt

Descending (younger): Son, Daughter, Grandson, Granddaughter, Nephew, Niece

Same generation: Brother, Sister, Cousin, Husband, Wife, Brother-in-law, Sister-in-law

3. Gender Indicators in Problems

If gender not stated directly, look for clues: "his wife", "her brother", "she said"

4. Types of Questions

Type 1 — Direct:

"A is the son of B. B is the sister of C. C is the father of D. How is A related to D?"

A→B(mother/aunt of A → B is female) →... Draw it out.

Type 2 — Pointing/Reference:

"Pointing to a man, A said 'His mother is the only daughter of my mother.'"

Only daughter of A's mother = A herself.

So A is the mother of the man. A is the man's mother.

Type 3 — Coded Blood Relations:

+ = father, - = mother, × = brother, ÷ = sister

A + B means A is father of B.

Decode each symbol and draw the family tree.

Type 4 — Number of Relations:

How many males in the family? How many children does X have?

Solved Examples

Q1: If A + B means A is the brother of B, A - B means A is the mother of B, A × B means A is the sister of B, then what does P + Q - R mean?

P+Q: P is brother of Q. Q-R: Q is mother of R.

So P is the uncle of R.

Q2: Pointing to a photo, Renu says "He is the son of my grandfather's only child."

Renu's grandfather's only child = Renu's father or mother (only one child).

He is the son of that person → He is Renu's brother.

Previous Year Questions

SBI Clerk 2023: "A's mother is the sister of B's father. B's father has only one sister. How is A related to B?"

A's mother = B's father's sister. B's father → B. A's mother = B's paternal aunt.

B and A are cousins. A is B's cousin.

IBPS PO 2022: Coded blood relation with 4 symbols and 5-step chain.

Revision Notes

APPROACH:
1. Draw family tree as you read clues
2. Mark gender (square for male, circle for female)
3. Only assign relationship when SURE about gender
4. If gender ambiguous, consider both possibilities

COMMON PHRASES:
"Only daughter of my mother" = ME (if I have no sisters)
"Only son of his father" = that person is the only male child
"Son-in-law" = husband of daughter
"Mother-in-law" = wife's/husband's mother

CLASSIC PUZZLE:
"A said to B: Your mother's husband's sister is my aunt"
B's mother's husband = B's father. Father's sister = B's paternal aunt.
B's paternal aunt = A's aunt → A and B are cousins OR siblings.