Blood Relations | Reasoning and Military Aptitude Test for AFCAT PDF Download

Definition

Prerequisites

1. Relations of Paternal side
   Father’s father → Grandfather
   Father’s mother → Grandmother
   Father’s brother → Uncle
   Father’s sister → Aunt
   Children of uncle → Cousin
   Wife of uncle → Aunt
   Children of aunt → Cousin
   Husband of aunt → Uncle
2. Relations of Maternal side:
   Mother’s father → Maternal grandfather
   Mother’s mother → Maternal grandmother
   Mother’s brother → Maternal uncle
   Mother’s sister → Aunt
   Children of maternal uncle → Cousin
   Wife of maternal uncle → Maternal aunty
3. Relations:
   

The efficiency in doing the problems of blood relations depends upon the knowledge of the blood relations. Some of the important relations are given below:

1. My mother’s or father’s son is my Brother.
2. My mother’s or father’s daughter is my Sister.
3. My mother’s or father’s father is my Grandfather.
4. My mother’s or father’s sister is my Aunt.
5. My mother’s or father’s brother is my Uncle.
6. My son’s wife is my Daughter-in-law.
7. My daughter’s husband is my Son-in-law.
8. My brother’s son is my Nephew.
9. My brother’s daughter is my Niece.
10. My sister’s husband is my Brother-in-law.
11. My brother’s wife is my Sister-in-law.
12. My husband’s wife’s sister is my Sister-in-law.
13. My husband’s or wife’s brother is my Brother-in-law.
14. My uncle’s or aunt’s son or daughter is my Cousin.
15. My wife’s father or husband’s father is my Father-in-law.
16. My wife’s mother or husband’s mother is my Mother-in-law.
17. My father’s wife is my Mother.
18. My mother’s husband is my Father.
19. My son’s or daughter’s son is my Grandson.
20. My son’s or daughter’s daughter is my Grand-daughter.

Different Types of Questions with Explanation

Q.1. A is B’s daughter, B is C’s mother. D is C’s brother. How is D related to A?
(a) Father
(b) Grandfather
(c) Brother
(d) Son
Ans: c

A and C are both daughters of B. D being the brother of C  he is also a brother of A

Q.2. P is Q’s brother. R is Q’s mother. S is R’s father. T is S’s mother. How is P related to T
(a) Grand-daughter
(b) Great-grandson
(c) Grandson
(d) Grandmother
Ans: b

P is the brother of Q. Therefore, P is a male. R is the mother of P and Q and R are daughters of S. S is the son of T. S is the grandfather of P. Therefore, P is the great-grandson of T.

Q.3. A is B’s brother. C is D’s father. E is B’s mother. A and D are brothers. How is E related to C?
(a) Sister
(b) Sister-in-law
(c) Niece
(d) Wife
Ans: d

C is the father of A, B and D.
E is the mother of A, B and D.
Therefore, E is the wife of C.
Deductions:
(i) A and D are brothers of D
(ii) C is the father of A, B and D
(iii) C is the mother of A, B and D
(iv) E is wife of C

Q.4. A is the sister of B. B is the brother of C. C is the son of D. How is D related to A?
(a) Mother
(b) Daughter
(c) Son
(d) Uncle
Ans: a
As per the question, A is the sister of B and C whereas D is the father or mother of A, B and C. Therefore, D is the mother of B.

Q.5. B is the brother of A. whose only sister is mother of C. D is maternal grandmother of C. How is A related to D?
(a) Daughter-in-law
(b) Daughter
(c) Aunt
(d) Nephew
Ans: b
Although sex of A is not mentioned clearly in the question. On the basis of information given is A is daughter of B.

Q.6. A and B are sisters. R and S are brothers. A’s daughter is R’s sister. What is B’s relation to S?
(a) Mother
(b) Grandmother
(c) Sister
(d) Aunt
Ans: d
A and B are sisters.
A's daughter is R's sister hence she is S's sister also.
Then A has three children one daughter and two sons (R and S).
Hence, B is the aunt of S.

Q.7. E is the sister of B. A is the father of C. B is the son of C. How is A related to E?
(a) Grandfather
(b) Grand-daughter
(c) Father
(d) Great-grandfather
Ans: a
A is father of C, who is father of B that means A is Grandfather of B E is B’s sister, so A is also Grand father of E.

Q.8. Given that:
A is the mother of B.
C is the son of A.
D is the brother of E.
E is the daughter of B.
Who is grandmother of D?
(a) A
(b) B
(c) C
(d) D
Ans: a
E is the daughter of B and D is brother of E. Therefore, D is son of B and A is mother of B. Thus, A is grandmother of D.

Q.9. A is D’ brother. D is B’s father. B and C are sisters. How is A related to C?
(a) Son
(b) Grandson
(c) Father
(d) Uncle
Ans: d
B and C daughters of D .
A is brother of D .
Therefore A is uncle of C.

Q.10. A is B’s sister. C is B’s mother. D is C’s father. E is D’s mother, then how A is related to D?
(a) Grandfather
(b) Daughter
(c) Grandmother
(d) Granddaughter
Ans: d

From the information given, it can be concluded:
A is B's sister and their mother is C.
D is their grandfather and E is their great-grandmother.
So, A is the granddaughter of A.

Q.11. (i) F is the brother of A.
(ii) G is the daughter of A.
(iii) K is the sister of F.
(iv) G is the brother of C.

Who is the uncle of G?
(a) A
(b) C
(c) K
(d) F
Ans: d
G ⇒ brother of C.
C ⇒ daughter of A.
So, G ⇒ son of A.
F ⇒ brother of A.
Therefore, F is the uncle of G.

Q.12. A is father of C and D is son of B. E is brother of A. If C is sister of D, how is B related to E?
(a) Sister-in-law
(b) Sister
(c) Brother
(d) Brother-in-law
Ans: a
A is father of C and C is sister of D. So, A is father of D. But D is son of B. So, B is the mother of D and wife of A. Also, E is the brother of A. So, B is the sister-in-law of E. 

Q.13. C is wife of B. E is the son of C, A is the brother of B and father of D. What is the relationship of E to D?
(a) Mother
(b) Sister
(c) Brother
(d) Cousin
Ans: c
E is B and C.
A is uncle of E and Father of D.
Therefore E is cousin of D.

Q.14. M is the son of P. Q is the grand-daughter of O, who is the husband of P. How is M related to O?
(a) Son
(b) Daughter
(c) Mother
(d) Father
Ans: a
O is the Husband of P. M is the son of P.
Therefore, M is son of O.

Q.15. X and Y are brothers. R is the father of Y. S is the brother of T and maternal uncle of X. What is T to R?
(a) Mother
(b) Wife
(c) Sister
(d) Brother
Ans: b
R is the father of Y and X.
S is the maternal uncle of X and Y.
So, T is the mother of X and Y.
Thus, T is the wife of R.