Blood Relations – Study Notes for IBPS Clerk
Why You Need These Notes
In reasoning tests, “Blood Relations” questions check how well you can keep track of family ties.
They usually involve a few people standing in a line, a set of clues, and a question like “Who is X’s mother?”
The trick is to read each clue, map the relationships, and then answer in the fewest steps possible.
1. What Are Blood Relations?
| Relationship | Everyday Analogy |
|---|---|
| Parent (mother/father) | The person who raised you. |
| Sibling (brother/sister) | Your best friend who grew up with you. |
| Grandparent (grandmother/grandfather) | The parents of your parent. |
| Grandchild | Your child’s child. |
| Uncle/Aunt | Your parent’s sibling. |
| Cousin | The child of your uncle/aunt. |
| Niece/Neph | The child of your sibling. |
| First cousin once removed | A cousin who is one generation apart (e.g., your cousin’s child). |
Tip – Think in a tree:
- Root = grandparents
- Branches = parents
- Leaves = children
2. How to Read a Typical Blood‑Relation Question
-
List the Names
Write down all the people mentioned (often 4–6).
Example:A, B, C, D, E. -
Track the Clues
Write each clue as a short fact.
“A is older than B” →A > B(age order). -
Assign Relationships
Use a family tree or a grid.- Draw a vertical line for each generation.
- Write names on the appropriate generation.
-
Ask the Question
Once the tree is ready, the answer is just a lookup.
3. Common Clues & How to Decode Them
| Clue | What It Means | Quick Check |
|---|---|---|
| “X is the father of Y.” | X → Y (parent) | X ABOVE Y |
| “X is the mother of Y.” | X → Y (mother) | X ABOVE Y |
| “X is the brother/sister of Y.” | X ↔ Y (siblings) | Same generation |
| “X is the son/daughter of Y.” | X → Y (child) | X BELOW Y |
| “X is the uncle/aunt of Y.” | X is sibling of Y’s parent | X ABOVE Y’s parent |
| “X is the nephew/niece of Y.” | X is child of Y’s sibling | X BELOW Y’s sibling |
| “X is the cousin of Y.” | X and Y share a grandparent but are not siblings | Same generation, different parents |
| “X is the son/daughter of the brother of Y.” | X is Y’s nephew/niece | X BELOW Y’s sibling |
Remember – “Father” and “Mother” are the same as “son”/“daughter” but in the opposite direction.
4. Quick Strategy for Solving
-
Start from the Extremes
If a clue says “X is the eldest”, place X at the top of the tree. -
Chain the Relations
Use a chain like A → B → C to place everyone in order. -
Cross‑Check
If one clue says “A is older than B” and another “B is the son of A”, both must agree. -
Eliminate Possibilities
If a clue says “C is not X’s brother”, remove that possibility. -
Answer Quickly
Once the tree is drawn, the answer is a single lookup.
5. Tiny Example
Clues
- A is the mother of B.
- C is the brother of B.
- D is the son of C.
- E is the sister of A.
Step‑by‑Step
| Person | Generation | Relation |
|---|---|---|
| A | Parent | Mother of B |
| B | Child | Daughter of A |
| C | Parent | Brother of B → same generation as A |
| D | Child | Son of C |
| E | Parent | Sister of A → same generation as A |
Tree
(Parent Generation)
A ----- C ----- E
|
D
B (child of A)
Question – Who is the father of D?
Answer: C (C is the parent of D).
6. Common Mistakes to Avoid
| Mistake | Why It Happens | How to Fix |
|---|---|---|
| Mixing up mother/father with son/daughter | Forgetting direction of arrow | Draw a vertical line: parent above child. |
| Assuming “brother” means “male sibling” | Some questions use “sibling” instead of “brother” | Treat “brother” and “sibling” the same for placement. |
| Ignoring age clues | Age and relation are different | Keep “older/younger” separate from “parent/child.” |
| Over‑counting cousins | Cousins share grandparents but can be from different parents | Don’t put cousins on the same branch as parents. |
7. Quick Practice Problem
Clues
- X is the son of Y.
- Y is the mother of Z.
- W is the daughter of X.
- V is the brother of Y.
- Z is the niece of V.
Question – Who is the father of W?
Solution Sketch
- X → Y (X is child of Y).
- Y → Z (Y is parent of Z).
- W is child of X.
- V is sibling of Y.
- Z is niece of V → Z is child of V’s sibling → that sibling is Y.
Answer – X is the father of W.
8. Final Take‑away
- Draw a simple tree – the heart of every blood‑relation problem.