Reasoning is a subject where I always tell students: no book can teach it to you, only practice can. Blood relations is the best place to start, because one method solves almost every question in this chapter. Once your hand draws the family tree automatically, these questions take 30 to 40 seconds each, well inside my one-minute-per-question rule.
What this topic covers
Three types of questions:
- Direct statements: "A is the brother of B. B is the mother of C..." How is A related to C?
- Pointing or introducing: "Pointing to a photo, Ravi said..."
- Coded relations: "P + Q means P is the father of Q..." Decode an expression.
Sometimes there is also a small family puzzle with 6 to 8 members, but it is solved with the same tree.
The family tree method
- One row per generation. Grandparents at the top, then parents, then children.
- Gender: write + for male and − for female next to each name. If the question doesn't say, leave it blank.
- Couple: join husband and wife with a double line (=) on the same row.
- Siblings: join brothers and sisters with a single horizontal line on the same row.
- Parent to child: a vertical line going down one row.
Then you just walk from the person asked about to the other person and name the relation.
Relations you must know without thinking
- Father's or mother's brother: uncle (mother's brother is maternal uncle, mama).
- Father's or mother's sister: aunt.
- Brother's or sister's son: nephew. Brother's or sister's daughter: niece.
- Uncle's or aunt's child: cousin.
- Wife's or husband's brother: brother-in-law. Sister's husband is also brother-in-law.
- Son's wife: daughter-in-law. Daughter's husband: son-in-law.
- Father's father: grandfather. Son's son: grandson.
- "Only son of my father" or "only daughter of my mother" usually means the speaker himself or herself, or the speaker's own sibling. Read carefully.
How it is asked in the exam
Example 1: pointing to a person
Pointing to a man, Ravi says, "His mother is the only daughter of my mother." How is Ravi related to the man?
- The only daughter of Ravi's mother is Ravi's sister (Ravi is male, so it can't be Ravi himself).
- That sister is the man's mother.
- So Ravi is the brother of the man's mother: Ravi is his maternal uncle (mama).
Example 2: chain of statements
A is B's brother. C is A's mother. D is C's father. How is A related to D?
- Row 1: D (+).
- Row 2: C (−), D's daughter.
- Row 3: A (+) and B, C's children.
- A is the son of D's daughter, so A is D's grandson.
Example 3: coded relations
P + Q means P is the father of Q. P − Q means P is the wife of Q. P × Q means P is the brother of Q. P ÷ Q means P is the daughter of Q.
(a) What does A ÷ B + C mean?
- A ÷ B: A is the daughter of B.
- B + C: B is the father of C.
- So A and C are both children of B, and A is female. A is the sister of C.
(b) What does M − N + O × P mean?
- M − N: M is the wife of N.
- N + O: N is the father of O.
- O × P: O is the brother of P, so P is also N's child.
- M is the wife of P's father, so M is the mother of P.
Tip for coded questions: decode one symbol at a time, from left to right, and draw as you go. Don't try to hold the whole chain in your head.
Example 4: the gender trap
A is the sibling of B. B is the brother of C. How is A related to C?
A is C's sibling, but A's gender is not given. The answer is brother or sister, cannot be determined. Many students tick "brother" because the question says "brother" once. That mark is lost to an assumption.
Points to remember
- Never assume gender from a name. Names like Simran, Jaspreet or Navneet are used for both men and women in Punjab, and paper setters know it.
- Words like child, sibling, parent, spouse and cousin don't tell you the gender.
- Husband and wife are always on the same row. If your tree puts them on different rows, you misread a line.
- When a question says "only son" or "only daughter", stop and check whether it is the speaker.
Common mistakes
- Solving in your head for long chains. Draw it; it is faster.
- Mixing up son-in-law (daughter's husband) and brother-in-law (sister's husband or spouse's brother).
- Reading "P is the brother of Q" and "Q is the brother of P" as the same thing. The second one tells you Q's gender, not P's.
Practise straight after reading
Following the way I practised: list the types (direct, pointing, coded, puzzle), solve at least 20 questions of each type from your reasoning book, and then do 100 to 200 mixed questions from the reasoning quizzes on this site. Every time you get one wrong, redraw that tree in your notebook. Revise the notebook after 1, 7 and 30 days.