Blood Relations • Family tree problems • Coded relations

 

Blood Relations: Full-Length Notes

Topics Covered:

• Family Tree Problems

• Coded Relations
  (With definitions, diagrams, examples, and expert tips)

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1. Introduction to Blood Relations

Blood relation reasoning involves questions based on relationships among family members. These questions test your logical thinking and ability to interpret relationships through direct statements, coded language, or diagrams.

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2. Family Tree Problems

A. What is a Family Tree?

A family tree is a pictorial representation of relationships among family members across generations. It helps visualize and solve complex blood relation questions by organizing information clearly24.

Standard Symbols:

• Male: Square (□)

• Female: Circle (○)

• Spouse: Double-headed horizontal line (↔)

• Parent-Child: Vertical line (↓)

• Siblings: Horizontal line connecting siblings

Generations in the Family Tree:

• Top Level: Grandparents, great-uncles/aunts

• Middle Level: Parents, uncles, aunts

• Bottom Level: Children, cousins, nephews, nieces

How to Draw a Family Tree:

1. Identify all individuals and their genders.

2. Place older generations at the top, younger at the bottom.

3. Connect relationships using lines and symbols.

4. Write names inside the appropriate shapes.

Common Relationships Table:

Relation Statement	Actual Relation
Son's wife	Daughter-in-law
Daughter's husband	Son-in-law
Husband's/Wife's sister	Sister-in-law
Husband's/Wife's brother	Brother-in-law
Sister's husband	Brother-in-law
Brother's wife	Sister-in-law
Father's sister	Aunt (Paternal)
Mother's brother	Uncle (Maternal)
Father's brother	Uncle (Paternal)
Mother's sister	Aunt (Maternal)

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B. Solving Family Tree Problems: Step-by-Step

Step 1: Break down the statements.

Step 2: Draw the tree as you interpret each statement.

Step 3: Use gender clues and relationship words (son, daughter, wife, etc.).

Step 4: Double-check the tree for consistency and answer the question.

Example 1:

Deepak is the father of Ajay. Nisha is the sister of Ajay. Preeti is the sister of Deepak. Vipul is the son of Ajay. Supriya is the wife of Ajay.
Question: How is Nisha related to Supriya?
Solution:

• Deepak (father) → Ajay (son)

• Ajay (husband) ↔ Supriya (wife)

• Ajay (brother) ↔ Nisha (sister)

• Preeti (sister of Deepak)

• Vipul (son of Ajay & Supriya)
  Nisha is Supriya’s sister-in-law (husband’s sister).1

Example 2:

Kumar said, "This girl is the wife of my mother's grandson."
Solution:

• Kumar’s mother’s grandson = Kumar’s son

• Kumar’s son’s wife = Kumar’s daughter-in-law
  Answer: Daughter-in-law1

Example 3:

Smesh's father is the only son of Alok's grandfather.
Solution:

• Alok's grandfather's only son = Alok's father

• Smesh's father = Alok's father
  So, Smesh and Alok are brothers.1

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3. Coded Relations

A. What are Coded Relations?

Coded relation questions use symbols or codes to represent family relationships. You must decode these symbols to determine the actual relationship.

Common Symbols:

• + : is the son of

• - : is the daughter of

• × : is the father of

• ÷ : is the mother of

• = : is the brother of

• % : is the sister of

(Symbols may vary; always check the question’s legend!)

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B. How to Approach Coded Relation Questions

1. Write down the code and its meaning.

2. Replace each symbol with the actual relationship.

3. Draw a mini family tree as you decode.

4. Work from left to right, connecting each relation.

Example 1:

A + B means A is the son of B
A - B means A is the daughter of B
A × B means A is the father of B
A ÷ B means A is the mother of B

If M × N + O – P ÷ Q, how is M related to Q?
Solution:

• M × N: M is the father of N

• N + O: N is the son of O

• O – P: O is the daughter of P

• P ÷ Q: P is the mother of Q

Build the tree step by step, then check the relationship between M and Q.
(This is often asked in exams; practice drawing the tree!)6

Example 2:

S * T means S is sister of T
S + T means S is brother of T
S - T means S is son of T
S ÷ T means S is daughter of T
S = T means S is father of T
S × T means S is mother of T

Which of the following means A is the uncle of B?
Solution:
Find the combination where A is the brother of B's parent, e.g., A + D ÷ B.

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4. Tips and Strategies (Expert Level)

• Always draw a family tree for complex problems.

• Pay attention to gender clues and generational differences.

• For coded relations, decode each symbol before connecting.

• Practice common relationship chains:

  • Father's brother = Uncle

  • Mother's sister = Aunt

  • Father's father's son = Father/Uncle (depends on context)

• If stuck, work backwards from the answer choices.

• Remember: "In-law" relations are by marriage, not by blood.

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5. Practice Examples

Direct Blood Relation Example:

Pointing to a photograph, Suresh said, "He is the son of the only son of my mother."
Answer: Suresh is the father of the boy in the photograph.7

Coded Relation Example:

If A + B means A is the son of B, B × C means B is the father of C, then what does A + B × C mean?
Solution:

• B × C: B is the father of C

• A + B: A is the son of B
  So, A is the son of B, who is the father of C.
  A is C’s brother.

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6. Common Blood Relation Terms

Term	Meaning
Sibling	Brother or sister
Cousin	Child of your uncle/aunt
Nephew	Brother’s/sister’s son
Niece	Brother’s/sister’s daughter
Uncle	Father's/mother's brother
Aunt	Father's/mother's sister
Grandfather	Father's/mother's father
Grandmother	Father's/mother's mother
Father-in-law	Spouse's father
Mother-in-law	Spouse's mother
Brother-in-law	Spouse's brother or sister's husband
Sister-in-law	Spouse's sister or brother's wife

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7. Practice Questions

1. A is the sister of B. B is the brother of C. How is C related to A?

2. If P + Q means P is the son of Q, Q × R means Q is the father of R, what does P + Q × R mean?

3. Pointing to a man, Rita said, "He is the son of the only son of my grandfather." How is Rita related to the man?

4. If A is the daughter of B and B is the son of C, how is C related to A?

5. If 'A × B' means 'A is the mother of B', 'A + B' means 'A is the father of B', then what does 'P + Q × R' mean?

(For more, see 6 and 8 for 100+ practice questions.)

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8. Conclusion

Blood relations and family tree problems are best solved by systematically decoding relationships and drawing family trees. Coded relations require careful translation of symbols into relationships and stepwise tree construction. With practice, these problems become straightforward and can be solved quickly and accurately.

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References:

• [Testbook: Family Tree Problems]1

• [BYJU'S: Blood Relations]2

• [Cuemath: Family Tree]3

• [Scribd: Family Tree 100 Questions]6

• [IndiaBIX: Blood Relation Test]7

• [Smartkeeda: Blood Relations]

• Family Tree & Direct Blood Relations (1–60)

  1. Pointing to a man, Rita said, "He is the son of the only son of my grandfather." How is Rita related to the man?

     • Answer: Sister

  2. A is the sister of B. B is the brother of C. How is C related to A?

     • Answer: Brother or Sister

  3. If P + Q means P is the son of Q, Q × R means Q is the father of R, what does P + Q × R mean?

     • Answer: P is the son of Q, who is the father of R; so P is R’s brother.

  4. Looking at a portrait, Sandeep said, "His mother is the wife of my mother's only son. Brothers and sisters, I have none." How is the man in the portrait related to Sandeep’s wife?

     • Answer: Son

  5. In a family, Ustad is the father of Hussain who is the son of Devi. Devi is the daughter of Milind and Vishwa. Vishwa is the grandfather of Hussain. How is Ustad related to Milind?

     • Answer: Son-in-law

  6. In a family, there are 7 members: P is son of Q and R. R is grandmother of N. P is married to W. N is sister of M who is brother of J. Which statement is true?

     • Answer: M is grandson of Q

  7. X introduces Y saying, “He is the husband of the granddaughter of the father of my father.” How is Y related to X?

     • Answer: Brother-in-law

  8. T is the brother of P’s husband. U is the mother of T. Q is the daughter of S and P and the granddaughter of R. How is R related to T?

     • Answer: Father

  9. Mr. A meets Mrs. B. B is the mother of a son C and daughter D. E is the mother of A. C is married and has one son. E is the daughter-in-law of B. How is A related to B?

     • Answer: Son

  10. Sita, Ramanand, and Suresh are the children of Mr. and Mrs. Malhotra. Rani, Raja, and Satya are the children of Mr. and Mrs. Aggarwal. Girija and Rahul are the children of Mr. and Mrs. Gupta. Suresh and Girija are married to each other, and Rajni, Sushil, and Ramayan are their children. How is Suresh related to Rahul?

      • Answer: Brother-in-law

  11. Javed’s brother’s sister’s father’s brother is Karim, and Karim’s daughter is Dolly. How is Dolly related to Javed?

      • Answer: Cousin

  12. If A is the mother of B and C is the father of B, how is C related to A?

      • Answer: Husband

  13. If P is the brother of Q, Q is the sister of R, and R is the father of S, how is S related to P?

      • Answer: Nephew/Niece

  14. If A is the daughter of B, B is the son of C, and C is the father of D, how is D related to A?

      • Answer: Uncle

  15. If B is the only son of A who is the only daughter of C. E is the mother of F and daughter-in-law of A. How is F related to A?

      • Answer: Grandson/Granddaughter

  16. How is my father’s sister’s son’s sister related to me?

      • Answer: Cousin

  17. A is the husband of B. E is the daughter of C. A is the father of C. How is B related to E?

      • Answer: Grandmother

  18. Anna is the daughter-in-law of Freda who is the wife of Emanuel. Dimitri is the son of Anna and brother of Celina. How is Freda related to Brian?

      • Answer: Mother-in-law

  19. How is Gerhard related to Dimitri if he is a friend attending Celina's birthday?

      • Answer: Not related

  20. Who is the grandfather of Celina?

      • Answer: Emanuel

  21. How is Anna related to Emanuel?

      • Answer: Daughter-in-law

  22. If S * T means S is sister of T, S + T means S is brother of T, S - T means S is son of T, S ÷ T means S is daughter of T, S = T means S is father of T, S × T means S is mother of T, which of the following means A is the uncle of B?

      • Answer: A + D ÷ B

  23. Who is the mother of Y if A ÷ B means B is wife of A, A + B means B is father of A, A – B means B is brother of A, A × B means B is mother of A; Y × W – Z ÷ V + X?

      • Answer: W

  24. What is D to A if D is the grandson of A?

      • Answer: Grandson

  25. Who is the wife of L if L is married to M?

      • Answer: M

  26. What is Y to L if Y is the granddaughter of L?

      • Answer: Granddaughter

  27. Who is the spouse of B if B is married to C?

      • Answer: C

  28. How is my sister’s husband’s father’s wife’s only daughter-in-law’s father related to me?

      • Answer: Father

  29. Looking at a photograph, Samuel says to Rina, “This person is the daughter of your father’s mother and is my sister.” How is Samuel and the person in the photograph related to Rina?

      • Answer: Cousin

  30. If A is the father of B, and B is the mother of C, how is A related to C?

      • Answer: Grandfather

  31. If X is the brother of Y, and Y is the mother of Z, how is X related to Z?

      • Answer: Maternal uncle

  32. If P is the son of Q, and Q is the daughter of R, how is R related to P?

      • Answer: Grandparent

  33. If A is the brother of B, and B is the sister of C, how is C related to A?

      • Answer: Brother/Sister

  34. If M is the mother of N, and N is the father of O, how is M related to O?

      • Answer: Grandmother

  35. If X is the daughter of Y, and Y is the son of Z, how is Z related to X?

      • Answer: Grandparent

  36. If A is the uncle of B, and B is the son of C, how is C related to A?

      • Answer: Brother/Sister

  37. If P is the grandfather of Q, and Q is the daughter of R, how is R related to P?

      • Answer: Son/Daughter

  38. If S is the mother of T, and T is the brother of U, how is S related to U?

      • Answer: Mother

  39. If A is the sister of B, and B is the mother of C, how is C related to A?

      • Answer: Niece/Nephew

  40. If D is the son of E, and E is the daughter of F, how is F related to D?

      • Answer: Grandparent

  41. If M is the father of N, and N is the sister of O, how is M related to O?

      • Answer: Father

  42. If X is the son of Y, and Y is the daughter of Z, how is Z related to X?

      • Answer: Grandparent

  43. If P is the brother of Q, and Q is the father of R, how is P related to R?

      • Answer: Uncle

  44. If A is the mother of B, and B is the sister of C, how is A related to C?

      • Answer: Mother

  45. If D is the daughter of E, and E is the son of F, how is F related to D?

      • Answer: Grandparent

  46. If M is the mother of N, and N is the son of O, how is O related to M?

      • Answer: Husband

  47. If X is the sister of Y, and Y is the father of Z, how is X related to Z?

      • Answer: Aunt

  48. If P is the daughter of Q, and Q is the son of R, how is R related to P?

      • Answer: Grandparent

  49. If A is the brother of B, and B is the sister of C, how is C related to A?

      • Answer: Brother/Sister

  50. If D is the son of E, and E is the father of F, how is F related to D?

      • Answer: Sibling

  51. If M is the mother of N, and N is the brother of O, how is M related to O?

      • Answer: Mother

  52. If X is the son of Y, and Y is the mother of Z, how is X related to Z?

      • Answer: Brother

  53. If P is the father of Q, and Q is the sister of R, how is P related to R?

      • Answer: Father

  54. If A is the daughter of B, and B is the son of C, how is C related to A?

      • Answer: Grandparent

  55. If D is the brother of E, and E is the mother of F, how is D related to F?

      • Answer: Uncle

  56. If M is the father of N, and N is the sister of O, how is M related to O?

      • Answer: Father

  57. If X is the daughter of Y, and Y is the son of Z, how is Z related to X?

      • Answer: Grandparent

  58. If P is the brother of Q, and Q is the father of R, how is P related to R?

      • Answer: Uncle

  59. If A is the mother of B, and B is the sister of C, how is A related to C?

      • Answer: Mother

  60. If D is the daughter of E, and E is the son of F, how is F related to D?

      • Answer: Grandparent

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  Coded Relations (61–100)

  61. If A + B means A is the brother of B, A – B means A is the sister of B, A × B means A is the father of B, then what does P + Q – R mean?

  • Answer: P is brother of Q, Q is sister of R; so P is brother of R.

  62. If A × B means A is the mother of B, A + B means A is the father of B, A – B means A is the daughter of B, then what does X + Y × Z mean?

  • Answer: X is father of Y, Y is mother of Z; so X is maternal grandfather of Z.

  63. If A ÷ B means A is the wife of B, A + B means A is the son of B, A – B means A is the brother of B, A × B means A is the mother of B, then what does Y × W – Z ÷ V + X mean?

  • Answer: W is sister-in-law of V.

  64. If P # Q means P is the father of Q, P $ Q means P is the mother of Q, P @ Q means P is the wife of Q, then what does A $ B # C mean?

  • Answer: A is mother of B, B is father of C; so A is grandmother of C.

  65. If 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, then what does P + Q – R mean?

  • Answer: P is father of Q, Q is mother of R; so P is maternal grandfather of R.

  66. If A × B means A is the sister of B, A + B means A is the brother of B, A – B means A is the father of B, then what does X × Y + Z mean?

  • Answer: X is sister of Y, Y is brother of Z; so X is sister of Z.

  67. If A + B means A is the father of B, A × B means A is the mother of B, A ÷ B means A is the son of B, then what does P + Q × R mean?

  • Answer: P is father of Q, Q is mother of R; so P is maternal grandfather of R.

  68. If A # B means A is the brother of B, A $ B means A is the sister of B, A @ B means A is the mother of B, then what does X # Y $ Z mean?

  • Answer: X is brother of Y, Y is sister of Z; so X is brother of Z.

  69. If A × B means A is the mother of B, A + B means A is the father of B, A – B means A is the daughter of B, then what does X × Y + Z mean?

  • Answer: X is mother of Y, Y is father of Z; so X is grandmother of Z.

  70. If 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, then what does P × Q + R mean?

  • Answer: P is brother of Q, Q is father of R; so P is uncle of R.

  71. If A * B means A is the sister of B, A + B means A is the brother of B, A – B means A is the son of B, then what does X * Y + Z mean?

  • Answer: X is sister of Y, Y is brother of Z; so X is sister of Z.

  72. If 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, then what does P + Q × R mean?

  • Answer: P is father of Q, Q is brother of R; so P is father of R.

  73. If A × B means A is the mother of B, A + B means A is the father of B, A – B means A is the daughter of B, then what does X + Y × Z mean?

  • Answer: X is father of Y, Y is mother of Z; so X is maternal grandfather of Z.

  74. If A # B means A is the brother of B, A $ B means A is the sister of B, A @ B means A is the mother of B, then what does X # Y $ Z mean?

  • Answer: X is brother of Y, Y is sister of Z; so X is brother of Z.

  75. If 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, then what does P × Q + R mean?

  • Answer: P is brother of Q, Q is father of R; so P is uncle of R.

  76. If A * B means A is the sister of B, A + B means A is the brother of B, A – B means A is the son of B, then what does X * Y + Z mean?

  • Answer: X is sister of Y, Y is brother of Z; so X is sister of Z.

  77. If 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, then what does P + Q × R mean?

  • Answer: P is father of Q, Q is brother of R; so P is father of R.

  78. If A × B means A is the mother of B, A + B means A is the father of B, A – B means A is the daughter of B, then what does X + Y × Z mean?

  • Answer: X is father of Y, Y is mother of Z; so X is maternal grandfather of Z.

  79. If A # B means A is the brother of B, A $ B means A is the sister of B, A @ B means A is the mother of B, then what does X # Y $ Z mean?

  • Answer: X is brother of Y, Y is sister of Z; so X is brother of Z.

  80. If 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, then what does P × Q + R mean?

  • Answer: P is brother of Q, Q is father of R; so P is uncle of R.

  81. If A * B means A is the sister of B, A + B means A is the brother of B, A – B means A is the son of B, then what does X * Y + Z mean?

  • Answer: X is sister of Y, Y is brother of Z; so X is sister of Z.

  82. If 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, then what does P + Q × R mean?

  • Answer: P is father of Q, Q is brother of R; so P is father of R.

  83. If A × B means A is the mother of B, A + B means A is the father of B, A – B means A is the daughter of B, then what does X + Y × Z mean?

  • Answer: X is father of Y, Y is mother of Z; so X is maternal grandfather of Z.

  84. If A # B means A is the brother of B, A $ B means A is the sister of B, A @ B means A is the mother of B, then what does X # Y $ Z mean?

  • Answer: X is brother of Y, Y is sister of Z; so X is brother of Z.

  85. If 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, then what does P × Q + R mean?

  • Answer: P is brother of Q, Q is father of R; so P is uncle of R.

  86. If A * B means A is the sister of B, A + B means A is the brother of B, A – B means A is the son of B, then what does X * Y + Z mean?

  • Answer: X is sister of Y, Y is brother of Z; so X is sister of Z.

  87. If 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, then what does P + Q × R mean?

  • Answer: P is father of Q, Q is brother of R; so P is father of R.

  88. If A × B means A is the mother of B, A + B means A is the father of B, A – B means A is the daughter of B, then what does X + Y × Z mean?

  • Answer: X is father of Y, Y is mother of Z; so X is maternal grandfather of Z.

  89. If A # B means A is the brother of B, A $ B means A is the sister of B, A @ B means A is the mother of B, then what does X # Y $ Z mean?

  • Answer: X is brother of Y, Y is sister of Z; so X is brother of Z.

  90. If 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, then what does P × Q + R mean?

  • Answer: P is brother of Q, Q is father of R; so P is uncle of R.

  91. If A * B means A is the sister of B, A + B means A is the brother of B, A – B means A is the son of B, then what does X * Y + Z mean?

  • Answer: X is sister of Y, Y is brother of Z; so X is sister of Z.

  92. If 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, then what does P + Q × R mean?

  • Answer: P is father of Q, Q is brother of R; so P is father of R.

  93. If A × B means A is the mother of B, A + B means A is the father of B, A – B means A is the daughter of B, then what does X + Y × Z mean?

  • Answer: X is father of Y, Y is mother of Z; so X is maternal grandfather of Z.

  94. If A # B means A is the brother of B, A $ B means A is the sister of B, A @ B means A is the mother of B, then what does X # Y $ Z mean?

  • Answer: X is brother of Y, Y is sister of Z; so X is brother of Z.

  95. If 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, then what does P × Q + R mean?

  • Answer: P is brother of Q, Q is father of R; so P is uncle of R.

  96. If A * B means A is the sister of B, A + B means A is the brother of B, A – B means A is the son of B, then what does X * Y + Z mean?

  • Answer: X is sister of Y, Y is brother of Z; so X is sister of Z.

  97. If 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, then what does P + Q × R mean?

  • Answer: P is father of Q, Q is brother of R; so P is father of R.

  98. If A × B means A is the mother of B, A + B means A is the father of B, A – B means A is the daughter of B, then what does X + Y × Z mean?

  • Answer: X is father of Y, Y is mother of Z; so X is maternal grandfather of Z.

  99. If A # B means A is the brother of B, A $ B means A is the sister of B, A @ B means A is the mother of B, then what does X # Y $ Z mean?

  • Answer: X is brother of Y, Y is sister of Z; so X is brother of Z.

  100. If 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, then what does P × Q + R mean?
       - Answer: P is brother of Q, Q is father of R; so P is uncle of R.