Blood Relations

Table of Contents

1. 1: Foundation & Basic Family Structures
2. 2: Family Tree & Diagrammatic Representation
3. 3: Coded Blood Relations
4. 4: Puzzle Based Blood Relations (Complex)
5. 5: Miscellaneous & Data Sufficiency
6. Official Blood Relations Practice Lab (50 MCQs)

1.1 What Are Blood Relations?

Blood relations refer to connections through birth (consanguinity) or marriage (affinity). In exams, you are typically given a set of statements describing relationships among family members, and you must answer questions about how two individuals are related (e.g., “How is A related to B?”).

The key to solving blood relations is to:

· Identify genders (male, female) – often given indirectly (e.g., “A is the father of B” implies A is male).
· Map relationships systematically, usually using a family tree.
· Track generations – older vs. younger.

1.2 Basic Family Relationships (Core Vocabulary)

Memorize these foundational relationships and their implications:

1.3 Gender Identification

Many blood‑relation questions require knowing the gender of a person. The statements often imply gender:

· Male indicators: father, brother, son, husband, uncle, grandfather, nephew, father‑in‑law, brother‑in‑law (when referring to spouse’s brother), son‑in‑law.
· Female indicators: mother, sister, daughter, wife, aunt, grandmother, niece, mother‑in‑law, sister‑in‑law (when referring to spouse’s sister), daughter‑in‑law.
· Neutral indicators: parent, child, sibling, cousin – gender unknown unless specified.

Sometimes gender is revealed indirectly: “A is the mother of B” tells us A is female; “A has two children” doesn’t specify gender.

1.4 Generations and Levels

It’s crucial to understand which generation each person belongs to. Typically:

· Own generation: self, siblings, cousins, spouse.
· One generation above: parents, uncles, aunts.
· Two generations above: grandparents, great‑uncles, etc.
· One generation below: children, nieces, nephews.
· Two generations below: grandchildren.

Keeping a mental or drawn tree helps to avoid confusion like confusing uncle with grandfather.

1.5 Common Relationship Pairs (Rules)

· Parent‑child: If A is the father/mother of B, then B is the son/daughter of A.
· Sibling: If A is the brother/sister of B, then they share at least one parent.
· Spouse: If A is the husband/wife of B, they are married.
· Grandparent‑grandchild: If A is the grandfather/grandmother of B, then A is parent of B’s parent.
· Uncle/Aunt – Niece/Nephew: If A is the uncle/aunt of B, then A is sibling of B’s parent.

These can be combined: e.g., “A is the brother of B’s father” → A is the uncle of B.

1.6 Step‑by‑Step Approach for Simple Blood Relations

For basic questions (direct relationship between two persons given a chain of statements), follow these steps:

1. Read the statements carefully and note the relationships.
2. Start with a person mentioned often or with clear connections.
3. Draw a small family tree (we’ll cover full tree in subtopic 2) using symbols:
   · Use square for male, circle for female (or simply M/F).
   · Use horizontal line for marriage.
   · Use vertical line for parent‑child.
4. Place known genders as soon as you can infer them.
5. Link relationships step by step.
6. Answer the question by tracing the relationship between the two individuals in question.

1.7 Worked Examples – Foundation Level

Example 1 – Simple Chain

Question: “A is the father of B. B is the sister of C. How is A related to C?”

• Step 1: A is father of B → A (male), B (child).
• Step 2: B is sister of C → B and C are siblings; B is female. Since B is sister, C could be brother or sister.
• Step 3: A is father of B and B is sibling of C, so A is also parent of C (unless half‑sibling, but usually full siblings assumed).
• Step 4: Therefore, A is father of C.
  Answer: Father

Example 2 – Mixed Generations

Question: “X is the mother of Y. Y is the wife of Z. Z is the father of W. How is X related to W?”

• Step 1: X mother of Y → X (female), Y (child).
• Step 2: Y wife of Z → Y female, Z male (husband).
• Step 3: Z father of W → Z male, W child.
• Step 4: Y is wife of Z, and Z is father of W. Assuming W is child of Z and Y (common in exams unless specified otherwise), then Y is mother of W.
• Step 5: X is mother of Y, so X is grandmother of W.
  Answer: Grandmother

Example 3 – In‑Laws

Question: “A is the brother of B. C is the daughter of A. D is the wife of B. How is C related to D?”

• Step 1: A brother of B → A and B are male siblings (A male).
• Step 2: C daughter of A → A father of C; C female.
• Step 3: D wife of B → D female, B male.
• Step 4: B is the brother of A. So B is the uncle of C (brother of father).
• Step 5: D is wife of B, so D is aunt (by marriage) of C.
• Answer: Niece (C is child of A, D is wife of B, so D is C’s aunt. Thus, C is D’s niece).

Example 4 – Self‑Reference

Question: “Pointing to a photograph, a man said, ‘His father is the only son of my mother.’ How is the man related to the person in the photograph?”

• Step 1: Let the man = M. The person in photograph = P.
• Step 2: “His father” = P’s father.
• Step 3: “The only son of my mother” – M’s mother has only one son, who is M himself (since M is male). So “the only son of my mother” = M.
• Step 4: Thus, P’s father = M. So M is the father of P.
  Answer: Father

1.8 Common Mistakes and How to Avoid Them

1.9 Quick Practice – Foundation Level

1. “Ravi is the father of Anjali. Anjali is the mother of Kiran. How is Ravi related to Kiran?” (Ans: Ravi is grandfather of Kiran.)
2. “Sita is the wife of Ram. Ram is the brother of Lakshman. How is Sita related to Lakshman?” (Ans: Sita is sister‑in‑law of Lakshman (brother’s wife).)
3. “A is the daughter of B. B is the mother of C. C is the brother of D. How is A related to D?” (Ans: A is sister of D.)
4. “Pointing to a woman, a man said, ‘She is the daughter of my only son.’ How is the man related to the woman?” (Ans: The man is the grandfather of the woman.)
5. “P is the son of Q. Q is the sister of R. R is the mother of S. How is P related to S?” (Ans: P and S are cousins.)

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Summary of Subtopic 1

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2: Family Tree & Diagrammatic Representation

2.1 Why Use a Family Tree?

In competitive exams, blood relation problems often involve 5–10 individuals with multiple interlinked statements. Trying to solve them mentally or with text alone leads to errors. A family tree:

· Visualizes generations – you can see who is above, below, or same level.
· Clarifies gender – using standard symbols.
· Shows connections – marriage, parent‑child, sibling bonds at a glance.
· Simplifies complex chains – like “A is the mother‑in‑law of B” becomes obvious.

2.2 Standard Symbols (Adopted by Most Exams)

We will use a simple, widely accepted notation:

· Square □ or capital M – Male
· Circle ○ or capital F – Female
· Double horizontal line ══ – Marriage
· Vertical line | – Parent‑child connection
· Horizontal line connecting below parents – Sibling connection

Example Visual Representation:

   (Father)□ ────── ○(Mother)
            │
      ┌─────┼─────┐
      □     ○     □
   (Son) (Dau) (Son)

2.3 Step‑by‑Step Method to Draw a Family Tree

1. Start with the person who appears most frequently or the one with the most direct links.
2. Place them at the appropriate generation level. Often we start with a reference person at the center.
3. Add relationships one by one:
   · For “A is the father of B”: place A above B (one generation up), connect with vertical line. Mark A as male.
   · For “A is the brother of B”: place A and B at same generation, under same parents.
   · For “A is the wife of B”: connect A and B with a marriage line; note genders.
4. If a relationship involves an in‑law, treat the spouse as a connector.
5. Use “?” or “unknown” for persons whose relationship is not yet placed; update as you get more clues.
6. Check consistency – ensure no contradictions.
7. Answer the question by tracing the required relationship from one individual to another.

2.4 Example – Building a Family Tree

Statements:

1. A is the father of B.
2. B is the sister of C.
3. C is the mother of D.
4. D is the wife of E.
5. E is the brother of F.

Construction:

• A (Male) is father of B (Female) and C (Female).
• C is mother of D (Female).
• D is married to E (Male).
• E and F are siblings.

2.5 Handling Multiple Generations – Vertical Alignment

It’s helpful to keep generations aligned vertically:
· Generation +2: Grandparents
· Generation +1: Parents, uncles, aunts
· Generation 0: Self and siblings, cousins
· Generation -1: Children, nieces, nephews
· Generation -2: Grandchildren

2.6 Representing Unknown Parents / Siblings

When parents are not mentioned, we can use placeholder parents or simply note them as siblings with a horizontal bracket or line.

2.7 Common Family Tree Patterns

Pattern 1 – Nuclear Family

  □ Father ─── ○ Mother
       │
  ┌────┼────┐
  □    ○    □
 Son Dau   Son

Pattern 2 – Extended with In‑laws

   □ F ─── ○ M
      │
   ┌──┴──┐
   ○ A   □ B
        │
        ○ C ─── □ D

(A is sister of B; B is father of C; C is wife of D).

2.8 Worked Examples – Using Family Tree

Example 1 – Moderate

Statements:
· P is the father of Q.
· Q is the mother of R.
· R is the sister of S.
· S is the brother of T.
· T is the daughter of U.
· U is the wife of V.

Question: How is P related to V?

Analysis:

• P is father of Q.
• Q is mother of R, S, T.
• T is daughter of U, so U is a parent. Since Q is mother, U must be father? Wait, “U is the wife of V” says U is female. So V is male.
• If Q is mother and V is father, Q and V are married.
• P is father of Q, and Q is married to V.
• Therefore, V is the son‑in‑law of P.
  Answer: Son-in-law

Example 2 – Complex with In‑laws

Statements:
· A is the sister of B.
· B is the mother of C.
· C is the wife of D.
· D is the brother of E.
· E is the father of F.
· F is the daughter of G.

Question: How is A related to G?

Analysis:

• A (female) is sister of B (female).
• B is mother of C (female). A is aunt of C.
• C is wife of D (male). D is son-in-law of B.
• D and E are brothers.
• E is father of F, and G is parent of F? So G is wife of E.
• A's niece (C) is married to D, whose brother (E) is married to G.
• No direct blood relation.
  Answer: No direct blood relation (Connected through multiple marriages).

2.9 Common Mistakes in Diagrammatic Representation

2.10 Pro Tips

· User standard symbols (□/○ or M/F).
· Keep generations aligned.
· Update the tree as new clues arrive.
· If stuck, list all individuals and known connections first.

2.11 Practice Set – Family Tree

1. Question: A is the father of B. B is the brother of C. C is the daughter of D. D is the wife of E. E is the son of F. How is F related to A? (Ans: F is father of A.)
2. Question: P is the mother of Q. Q is the sister of R. R is the husband of S. S is the daughter of T. How is T related to P? (Ans: No direct blood relation.)
3. Question: M is the brother of N. N is the father of O. O is the wife of P. P is the son of Q. Q is the mother of R. How is M related to R? (Ans: No direct blood relation.)

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Summary of Subtopic 2

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3: Coded Blood Relations

3.1 What Are Coded Blood Relations?

In coded blood relations, instead of writing “A is the father of B”, the exam uses a symbolic code such as:

· A + B means A is the father of B
· A – B means A is the mother of B
· A × B means A is the brother of B
· A ÷ B means A is the sister of B
· etc.

The symbols vary across exams. You are given a key (a legend) that defines what each symbol means. You must interpret the expressions and determine the relationship between two persons.

Sometimes the code is expressed in a chain: A + B – C means A is father of B, and B is mother of C (so A is grandfather of C). You may also be asked to find the expression that correctly represents a given relationship.

3.2 Common Coding Schemes

Although the symbols differ, some common conventions are:

Important: Always verify the meaning from the question's legend.

Example Legend (Pattern A):

• P + Q → P is the father of Q
• P – Q → P is the mother of Q
• P × Q → P is the brother of Q
• P ÷ Q → P is the sister of Q
• P = Q → P is the wife of Q (or spouse)

Example Legend (Pattern B):

• A * B → A is the father of B
• A # B → A is the mother of B
• A @ B → A is the brother of B
• A $ B → A is the sister of B
• A & B → A is the husband of B
• A % B → A is the wife of B

3.3 Step‑by‑Step Approach to Solve Coded Blood Relations

1. Read the coding legend carefully – note what each symbol represents. Write it down for quick reference.
2. Start from the left and decode step by step. For a chain like A + B – C:
   • A + B → A is father of B.
   • B – C → B is mother of C.
   • Combine: A is father of B, B is mother of C → A is maternal grandfather of C.
3. Build a family tree as you decode, using the standard symbols (□ for male, ○ for female, etc.). This prevents mistakes when the chain is long.
4. Test Each Option: If the question asks for the expression that represents a given relationship, construct the expression step by step from the relationship or test each option by building a tree.
5. Be cautious with gender – codes often imply gender (e.g., + usually indicates male). Use that to assign genders in your tree.

3.4 Worked Examples – Decoding Chains

Example 1 – Basic Chain

• Legend: (+ father, – mother, × brother, ÷ sister, = wife)
• Question: P + Q – R × S. How is P related to S?
• Analysis:
  • P + Q → P is father of Q.
  • Q – R → Q is mother of R (Q female, P is father of Q).
  • R × S → R is brother of S (R male, sibling of S).
• Tree: P (Male) is father of Q (Female). Q is mother of R (Male) and S.
• Answer: P is the grandfather of S.

Example 2 – Including Spouse

• Question: A = B – C + D. How is A related to D?
• Analysis:
  • A = B → A is wife of B (A female, B male).
  • B – C → B is parent? (Wait, logic check: if B is male, B cannot be "mother").
  • Correction based on legend: If the legend says (–) is mother and (=) is wife, the question must be internally consistent. Let's assume (–) is parent.
• Answer: If B is father of C and C is father of D, then A (wife of B) is the grandmother of D.

Example 3 – Finding the Correct Expression

• Question: Which expression shows that “A is the maternal uncle of B”?
• Options:
  a) A + C – B
  b) A – C + B
  c) A × C – B
  d) A ÷ C – B
• Analysis: Maternal uncle is "mother's brother".
  • c) A × C – B means A is brother of C, and C is mother of B.
• Answer: c) A × C – B

Example 4 – Complex Chain with Multiple Codes

• Legend: (@ father, # mother, $ brother, % sister, & husband, * wife)
• Question: A & B # C $ D % E. How is A related to E?
• Analysis: A is husband of B (A male). B is mother of C. C is brother of D. D is sister of E.
• Tree: A and B are parents of C, D, and E.
• Answer: A is the father of E.

3.5 Common Pitfalls

3.6 Pro Tips

• Shorthand definitions: e.g., + : F, - : M.
• Work left to right, building the tree incrementally.
• Use the spouse as a connector for in-laws.
• Practice with varied coding schemes to build flexibility.

3.7 Practice Set – Coded Blood Relations

Legend for 1-4: (+ father, – mother, × brother, ÷ sister, = husband)

1. A + B – C × D: How is A related to D? (Ans: Father)
2. X = Y – Z + W: How is X related to W? (Ans: Grandfather)
3. P × Q ÷ R – S: How is P related to S? (Ans: Maternal uncle)
4. Maternal grandmother of N?: Which expression? A) M – O + N B) M – O × N C) M + O – N D) M ÷ O – N (Ans: A)
5. Legend (@ F, # M, $ B, % S, & H): A & B # C $ D % E. How is A related to D? (Ans: Father)

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Summary of Subtopic 3

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4: Puzzle Based Blood Relations (Complex)

4.1 What Are Puzzle Based Blood Relations?

These puzzles present a network of relationships involving many family members. Complexity arises from:
· Multiple individuals (6–10 persons).
· Intertwined relationships (e.g., mixing parents, in-laws, siblings).
· Additional constraints (ages, occupations, "only son/daughter").
· Incomplete information requiring logical deduction.

4.2 Types of Complex Puzzles

• Type 1: Pure Blood Relation Puzzles (Build the tree and find the relation).
• Type 2: Mixed Information (Combined with ages, professions, or seating).
• Type 3: "Only" / "Exactly" Conditions (Constraints like "A is the only son of B").
• Type 4: Negative Statements ("A is not the father of B").

4.3 Step‑by‑Step Methodology

1. List all individuals mentioned.
2. Identify direct relationships (spouse or parent-child).
3. Create a family tree using standardized symbols.
4. Place definite individuals first (those with clear genders/generations).
5. Use “only” clues to limit branches (e.g., "only son").
6. Infer implied relationships (e.g., brother of father = uncle).
7. Use process of elimination for ambiguous roles.
8. Verify consistency across all clues.

4.4 Worked Examples – Detailed Solutions

Example 1 – Moderate Puzzle

• Statements: A is father of B. B is sister of C. C is mother of D. D is wife of E. E is brother of F. F is daughter of G. G is husband of H. H is mother of I. I is only son of H.
• Trace:
  • A is father of B and C.
  • C is mother of D.
  • E and F are siblings, children of G and H.
  • I is the only son of H.
• Answer: tracing from A to I: A is father of C, C is mother of D, D is married to E (who is son of G/H). I is E's brother? (Wait: If I is the "only son," then E must BE I).

Example 2 – Structured Puzzle

• Statements: A and B are married. C is daughter. D is son. E is sister of D. F is mother of B. G is father of A. H is wife of G. I is brother of H.
• Connection: I is maternal uncle of A. C is A's child.
• Answer: Great-uncle (I is the great-uncle of C).

Example 3 – Puzzle with “Only” Condition

• Statements: R is the only son of P. S is the daughter of Q. T is the mother of R and S. U is the father of P and Q.
• Answer: T is the grandmother (if P and Q are siblings and T is mother of their children).

4.5 Common Mistakes & Pitfalls

4.6 Pro Tips for Complex Puzzles

• Assign Generation Numbers (Gen 1: Grandparents, Gen 2: Parents, etc.).
• Use a pencil for rough drafts as the tree may shift.
• Start with the oldest generation mentioned.
• Verify every single statement once the tree is complete.

4.7 Practice Set – Complex Puzzles

Puzzle 1:

• A and B are brothers. C sister of A. D father of B. E mother of C. F wife of D. G daughter of E. H son of F. I only child of H.
• Q1: How is G related to I? (Ans: Half-aunt)
• Q2: How is C related to H? (Ans: Half-sibling)

Puzzle 2:

• P is grandfather of Q. R is mother of S. T is father of P. U is daughter of Q. V is brother of R. W is wife of T. X is only son of V. Y is mother of U.
• Q1: How is Y related to R? (Ans: Daughter-in-law)
• Q2: How is T related to S? (Ans: Great-grandfather)

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Summary of Subtopic 4

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5: Miscellaneous & Data Sufficiency

5.1 What Are Miscellaneous Blood Relation Problems?

Miscellaneous problems include:

· Self‑reference / Pointing problems – e.g., “Pointing to a photograph, a man said, ‘He is the son of my father’s only daughter.’”
· Indirect statements – Relationships expressed through complex linguistic chains.
· Mixed roles – Integrating family bonds with other non‑family attributes (like neighbours).
· Ambiguous links – Using terms like “maternal”, “paternal”, or “great‑grand”.
· In‑law relations – Tricky uses of affinity-based connections.

These questions test your ability to parse language, apply logical deduction, and combine family trees with other constraints.

5.2 Self‑Reference / Pointing Problems

In these problems, a speaker points to a subject and makes a statement.

Step‑by‑Step Approach:

1. Identify the speaker and the subject.
2. Parse the statement inside‑out. Start with the innermost relation and work outward.
3. Replace pronouns with actual relationships as you go.
4. Draw a small tree if the logic gets complex.
5. Finalize the link between the speaker and the subject.

Example:

• Question: Pointing to a photograph, a man said, ‘His father is the only son of my mother.’ How is the man related to the person in the photograph?
• Analysis:
  • “The only son of my mother” = Speaker (The man).
  • “His father” = The man.
• Answer: Father

5.3 Indirect Statements & Complex Phrasing

Use substitution to simplify phrases.

Example 1: “A is the brother of B’s mother.”

• Let X = B’s mother.
• A is the brother of X.
• Answer: Maternal Uncle

Example 2: “A is the father of B’s husband’s sister.”

• Let H = B’s husband. S = H’s sister.
• A is the father of S.
• Since S and H are siblings, A is also the father of H.
• Answer: Father‑in‑law (Father of B's husband).

5.4 Multiple Generations with “Great‑grand”

Carefully count levels:
· Great-grandfather: 3 generations above (Parent of a Grandparent).
· Maternal great‑aunt: Mother’s mother’s sister.

5.5 Data Sufficiency in Blood Relations

Data Sufficiency (DS) tests whether given statements provide enough information to identify a unique relationship.

Standard Options:

• A: I alone is sufficient.
• B: II alone is sufficient.
• C: Both together are sufficient.
• D: Each alone is sufficient.
• E: Both together are NOT sufficient.

Approach:

1. Check Statement I alone for a unique answer.
2. Check Statement II alone.
3. Combine if neither is independently sufficient.
4. If multiple relationships are still possible, mark E.

5.6 Worked Examples – Miscellaneous

Example 1 – Pointing to Photo

• Question: Pointing to a woman, a man said, “She is the daughter of my father’s only son.” How is the man related to the woman?
• Analysis: “My father’s only son” is the man himself. So, “She is the daughter of the man.”
• Answer: Father

Example 2 – Indirect Relation

• Question: “A is the brother of B’s mother’s only sister.” How is A related to B?
• Analysis: B's mother has only one sister. A is the brother of that sister. Thus A is the brother of B's mother as well.
• Answer: Maternal uncle

Example 3 – Generation Gap

• Question: “X is the great‑grandfather of Y. Z is the mother of Y. How is X related to Z?”
• Analysis: X is 3 levels above Y. Z is 1 level above Y. So X is 2 levels above Z (parent of Z's parent).
• Answer: Grandfather

5.7 Worked Examples – Data Sufficiency

Example 1: How is A related to B?

• I: A is brother of C.
• II: C is mother of B.
• Result: Together they show A is the maternal uncle.
• Answer: C (Together)

Example 2: Who is the father of A?

• I: A is the son of B. (B could be father or mother).
• II: B is the father of C. (B is male).
• Result: Combining them identifies B as the father of A.
• Answer: C (Together)

Example 3: Who is the wife of A?

• I: A is brother of B.
• II: B is mother of C; C is daughter of A.
• Result: II alone shows A and B are the biological parents of C.
• Answer: B (Statement II alone)

5.8 Common Pitfalls in DS

• Assuming gender: "Parent" or "Child" is neutral. Always verify if the parent is male (father) or female (mother).
• Uniqueness: If any statement suggests A could be either parent or uncle, it is NOT sufficient.

5.9 Pro Tips

• For pointing problems, always use inside‑out parsing.
• For DS, treat each statement as an independent island first.
• Re-read the question: are you identifying the relationship (Sufficiency) or just the gender?

5.10 Practice Set – Miscellaneous & DS

Miscellaneous:

1. Woman says: “His mother is the only daughter of my mother.” (Ans: Mother)
2. Chain: A is brother of B’s father’s only sister. (Ans: Paternal uncle)
3. Chain: X is great‑grandmother of Y. Z is daughter of Y. (Ans: Great‑great‑grandmother)

Data Sufficiency:

1. Q: How is P related to Q? I: P brother of R. II: R mother of Q. (Ans: C)
2. Q: Who is brother of A? I: A is son of B. II: B has two sons, one is A. (Ans: E - Name of the other son unknown).
3. Q: Is A the father of B? I: A is parent of B. II: A is male. (Ans: C)

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Summary of Subtopic 5

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Complete Blood Relations – Final Recap

We have now covered all five subtopics required for mastery:

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Official Blood Relations Practice Lab (50 MCQs)