A family has eight members. E is the mother of F and G. A is the son-in-law of E. C is the daughter of G. D is the maternal grandfather of C. D has one son and one daughter. H is the sister-in-law of G. B is the niece of F. How is F related to A ?
- (1)Sister-in-law
- (2)Sister
- (3)Brother-in-law
- (4)Brother
Answer
Why
Correct — option (3), Brother-in-law.
Work through the clues, noting what each one fixes.
"C is the daughter of G" and "D is the maternal grandfather of C": C's mother is a daughter of D.
Is G that mother? If G were C's father, C's mother would have to be someone other than E (G's mother), F (G's sibling), A (a son-in-law), D (a grandfather), H (G's sister-in-law) or B (F's niece): a ninth person. The family has eight members, so G is C's mother and D's daughter.
D is G's father and E is G's mother, so D and E are the couple. E is also F's mother, so F and G are their children.
"D has one son and one daughter." G is the daughter, so F is the son.
"A is the son-in-law of E": A is married to E's daughter, G.
F is G's brother, and G is A's wife. A wife's brother is a brother-in-law, so F is A's brother-in-law.
The other clues fit: H, G's sister-in-law, is F's wife (the Hindi text says भाभी, a brother's wife), and B, F's niece, is a daughter of G and A. That makes eight: D, E, F, H, G, A, C, B.
The idea to remember: fix genders and generations first; a wife's brother is a brother-in-law, not a brother.
Why the others are wrong
- (1)Sister-in-law — Option (1) gets the link through marriage right but needs F to be female.
D has one son and one daughter, and the daughter is G, C's mother. F, D's other child, is therefore the son. A wife's brother is a brother-in-law, not a sister-in-law.
- (2)Sister — Option (2) makes F A's own sibling, and female. Neither holds.
A joins the family only by marriage: he is E's son-in-law, married to G. F is G's brother, so F is related to A through A's wife, and F is male.
- (4)Brother — Option (4) has F's gender right but makes F A's brother by birth.
A's parents do not appear in the clues; A enters the family as E's son-in-law. F is the brother of A's wife G, which makes F A's brother-in-law, not A's brother.
Concept
Blood-relation reasoning builds a family tree from clues. Each clue fixes a generation, a gender, a marriage, or some combination of these.
Some words fix gender: son, daughter, brother, sister, niece, nephew. "Maternal grandfather" fixes both a gender and a line: the mother's father.
In-law relations run through marriage. A son-in-law is a daughter's husband; a wife's brother and a sister's husband are both brothers-in-law.
A stated member count can settle what the clues alone leave open, as the eight-member limit does here.
RPSC's 2023 syllabus lists "Problems related to Relations" under Mental Ability in Reasoning & Mental Ability.
Hindi kinship words can separate the mother's side from the father's side where English uses one word. नाना is the mother's father and दादा the father's father; English calls both grandfather.
Words for relatives through marriage and through siblings split the same way. जीजा is a sister's husband and साला a wife's brother, both "brother-in-law" in English; भाभी is a brother's wife, one kind of sister-in-law, and भानजी a sister's daughter, one kind of niece.
Key facts
- D has one son and one daughter: the daughter is G, C's mother, so F is the son.
- A is E's son-in-law, married to G; F, G's brother, is A's brother-in-law.
- The eight-member count rules out G being C's father, which would need a ninth person as C's mother.
- The Hindi text calls H G's भाभी (brother's wife) and B F's भानजी (sister's daughter).
- The Hindi version prints option (3) as जीजा/साला; F, the brother of A's wife, is A's साला.
H as F's wife follows the Hindi word भाभी; the answer does not depend on it.
Study next
Common traps
- Assuming G is C's father. "C is the daughter of G" leaves G's gender open; the maternal-grandfather clue and the eight-member count make G the mother.
- Stopping at the sibling link. F is G's brother, but the relation asked is to A, G's husband, so it runs through a marriage.
- Guessing F's gender. It comes only from "D has one son and one daughter", once G is known to be the daughter.
A question can give a chain of relations and ask how two members are related, as this one does, or ask which listed statement the clues make certain.
A question can hide a gender until a count, such as the number of members, sons or couples, settles it.
Related PYQs
A, B, C, D, E and F are six members of a family. B is married to C. F is the mother of E and D is the daughter of F. A’s daughter is E and C’s son is A. There are two married couples in the family. Which of the following is correct ?
- (1) B is grandfather of E.
- (2) C is mother of A.
- (3) C is grandmother of D.
- (4) E is granddaughter of C.
Answer(4)
Same three-generation family-tree deduction. There a six-member family with two married couples leads to the one certain statement, E is granddaughter of C (RPSC's key: option (4)); here the clues settle a single relation, F to A.
Practice
- practice — not a real PYQ
In a family, K is the mother of L and M and has no other children. L is the only son of K. N is the husband of M. How is L related to N ?
- (a)Brother
- (b)Brother-in-law
- (c)Father-in-law
- (d)Cousin
Answer(2) — K's two children are L and M; L is the only son, so M is a daughter. N is M's husband and L is M's brother, so L is N's wife's brother: a brother-in-law.Option (1) ignores that the link runs through a marriage, option (3) puts L a generation too high, and option (4) is a relation through a parent's sibling.
- practice — not a real PYQ
X is the maternal grandfather of Z. Y is the only daughter of X. W is the father of Z. How is Y related to W ?
- (a)Sister
- (b)Sister-in-law
- (c)Mother
- (d)Wife
Answer(4) — A maternal grandfather is the mother's father, so Z's mother is a daughter of X. X has only one daughter, Y, so Y is Z's mother, and W, Z's father, is her husband. Option (1) makes Y W's sibling, option (2) an in-law, and option (3) puts her a generation above W.