Blood Relations: Family Puzzles, Coded Relations and Counting Members
Blood Relations: Family Puzzles, Coded Relations and Counting Members
Harder blood-relation sets give a whole family of six to eight people with scattered clues, or code every relation as a symbol. A third type counts the members or the males and females in a family, or the minimum people needed for a list of relations. All three are solved on one family tree.
1. Methods Box
| Type | Method |
|---|---|
| Family puzzle with clues | Place married couples first, then children; mark gender the moment a clue fixes it |
| Coded relations (A ★ B means A is the mother of B) | Translate each symbol in order and draw the link; then read the asked relation |
| Which expression shows "M is the father-in-law of N" | Test each option on a tree; check genders too |
| Count members, males and females | Count only from the finished tree; one person can hold several roles |
| Minimum members for a list of roles | Let each person play as many roles as possible across three generations |
One person can be a father, a son and a husband at once: count people, not roles
A married couple's child links both parents to everyone below
✗ The family has 2 fathers and 2 sons, so at least 4 people | ✓ A grandfather, father and son give 2 fathers and 2 sons with 3 people
✗ M ★ K ● N means M is N's mother-in-law, so the answer works for "father-in-law" too | ✓ The gender is part of the relation: a mother-in-law is not a father-in-law
हिंदी नोट: बड़े परिवार वाले प्रश्नों में पहले विवाहित जोड़े रखिए, फिर बच्चे। कूटबद्ध संबंधों में हर चिह्न का अर्थ क्रम से लिखिए। सदस्यों की गिनती में भूमिकाएँ नहीं, व्यक्ति गिनिए।
Exam Pointer: Verified NTPC patterns: six-member family puzzles with gender clues, asking for the number of male members (April 2016 CBT-1), and symbols coding family relations (March 2026 Graduate CBT-1, August 2025 UG CBT-1). The minimum-members variant is solved on the same counting method; the great-grandparent chains had no separate verified shift and are tagged syllabus-based.
Pariksha Pattern: Every Way NTPC Asks This Topic
Pattern 1: Family puzzles with scattered clues
[PYQ: NTPC CBT-1 16-Apr-2016 Shift-1]
Family for both questions: P is married to Q. R and S are their children. T is R's wife, and U is the son of R and T. V is S's daughter. Q is the mother of S, and S is a woman.
EXAM LEVEL
Q. How is U related to Q?
U is the son of R, who is Q's child. So U is Q's grandson.
Answer: Grandson
EXAMATLAS LEVEL
Q. How many males and how many females are in this family?
T is R's wife, so R is male and T female. Q is a mother, so female, and P, her husband, is male. U is a son (male); S and V are female. Males: P, R, U. Females: Q, S, T, V.
Answer: 3 males, 4 females
Pattern 2: Coded relations
[PYQ: NTPC Graduate CBT-1 17-Mar-2026 Shift-1 | NTPC UG CBT-1 11-Aug-2025 Shift-2]
Codes for both questions: A ★ B means A is the mother of B; A ◆ B means A is the brother of B; A ● B means A is the husband of B; A ▲ B means A is the daughter of B.
EXAM LEVEL
Q. If P ★ Q ◆ R, how is P related to R?
P is Q's mother and Q is R's brother, so P is also R's mother.
Answer: Mother
EXAMATLAS LEVEL
Q. Which expression shows that M is the father-in-law of N? (a) M ● K ★ L ● N (b) M ◆ K ★ N (c) N ▲ K ● M (d) M ★ K ● N
(a): M is K's husband, K is L's mother, and L is N's husband. So M is L's father and N's father-in-law. (b) makes M N's maternal uncle, (c) makes M N's mother, and (d) makes M N's mother-in-law (female).
Answer: (a)
Pattern 3: Counting members and minimum members
[PYQ: NTPC CBT-1 16-Apr-2016 Shift-1]
EXAM LEVEL
Q. A family has a grandfather and grandmother, their two sons, the sons' wives, and one daughter for each son. How many members, and how many females?
2 + 2 + 2 + 2 = 8 members. Females: the grandmother, two wives and two daughters, which is 5.
Answer: 8 members; 5 females
EXAMATLAS LEVEL
Q. What is the minimum number of people in a family with 2 fathers, 2 mothers, 2 sons, 1 grandfather, 1 grandmother and 1 daughter-in-law?
Take a grandfather and grandmother, their son, the son's wife and their son. Fathers: grandfather and son (2). Mothers: grandmother and the son's wife (2). Sons: the middle man and the boy (2). The son's wife is the daughter-in-law. That is 5 people.
Answer: 5
Pattern 4: Long chains across three or four generations
[Pattern: syllabus-based, PYQ-style]
EXAM LEVEL
Q. A is B's brother, C is A's mother, D is C's father and E is D's mother. How is A related to D?
D is the father of A's mother, so A is D's grandson (A is male, being a brother).
Answer: Grandson
EXAMATLAS LEVEL
Q. Using the same chain, how is E related to B, and how is B related to D?
E is the mother of D, who is the father of B's mother, so E is B's great-grandmother. B's gender is not given, so B is D's grandchild (grandson or granddaughter).
Answer: Great-grandmother; grandchild (gender not fixed)
60-Second Revision
- Place couples first, then children; fix gender from each clue.
- Coded relations: translate symbol by symbol; check genders.
- Count people, not roles; one person can be father, son and husband.
- Gender not given means you cannot name son or daughter.
Next Step: Blood Relations done. Solve the family-tree set in the ExamAtlas RRB NTPC 2026 mock tests; draw the tree first and every question in the set takes seconds.