Construct genealogical family trees, resolve paternal/maternal branches, and decode symbol-based relationship ciphers.
Core Theoretical Principles
Systematic principles and analytical strategies prescribed by the CBSE curriculum for Blood Relation.
Standard Family Tree Notations: • Male: $[+]$ or $\square$ • Female: $[-]$ or $\bigcirc$ • Married Couple: Double horizontal line $[A] = [B]$ • Siblings: Single horizontal line $A - B$ • Generational Shift: Vertical descent line $\downarrow$
Coded Relations Decoding Algorithm: In expressions like $G @ T \# P$, decode by substituting definitions from left to right or right to left, tracking gender and generation step-by-step.
Solved Illustrative Examples
Example 1 (Direct Verbal Clue)
Introducing a woman, a man said, 'Her husband is the only son of my father.' How is the woman related to the man?
Step 1: 'Only son of my father' $\implies$ the speaker himself (since the speaker is a man). Step 2: 'Her husband is [the speaker himself]'. Step 3: Therefore, the woman is the man's wife. Answer: (c) Wife.
Example 2 (Coded Blood Relation)
If 'A#B' means A is father of B, 'A*B' means A is brother of B, 'A@B' means A is mother of B. Which is correct about G@T#P?
Step 1: Decode $G @ T$: G is the mother of T (G is female, T is child). Step 2: Decode $T \# P$: T is the father of P (T is male). Step 3: Since T is male and G is mother of T, T is the son of G. Answer: (c) T is son of G.
Example 3 (Multi-Generation Pointer)
Pointing towards a person, a man said to a woman, 'His father is the son of my mother's only son.' How is the man related to that person?
Step 1: 'My mother's only son' $\implies$ the speaker himself. Step 2: 'The son of my mother's only son' $\implies$ speaker's son. Step 3: 'His father is [the speaker's son]'. Step 4: The person's father is the speaker's son $\implies$ The speaker is the grandfather of the person. Answer: (d) Grandfather.
Check Your Progress 3.3
Official CBSE Applied Mathematics Support Material Questions with Step-by-Step Solutions
CYP 3.3.1CBSE Textbook Question
R is the son of A's father's sister. S is son of D, who is the mother of G and grandmother of A. H is the father of T and grandfather of R. D is wife of H. How is R related to D?
1. D is grandmother of A and wife of H (grandfather of R). 2. Thus D and H are grandparents of R. 3. Since R is a male child of their daughter, R is the grandson of D. Answer: (c) Grandson.
CYP 3.3.2CBSE Textbook Question
A, B, C, D, E, F and G are members of a family of 4 adults and 3 children (F and G are boys). A and D are brothers; A is engineer. E is a doctor married to one brother and has 2 children. B is married to D and G is their child. Who is C?
1. Brothers are A and D. 2. B is married to D $\implies$ E is married to A. 3. E has 2 children (out of 3 children C, F, G). Since G is child of B & D, the other two children F and C belong to A & E. 4. Since two children are boys (F and G), C must be the female child (daughter). Answer: (c) E's daughter.
CYP 3.3.3CBSE Textbook Question
A and B are brothers. M is father of A and brother of S. F is sister of B and K is mother of S. What is the relationship between B and K?
1. M and S are children of K (mother of S). 2. A, B, and F are children of M. 3. Therefore, K is the grandmother of B, and B is the grandson of K. Answer: (b) Grandson and Grandmother.
Applied Problem-Solving Worksheet
Test your analytical mastery with graded problem sets for Blood Relation. Work through each problem systematically.
Speed & Accuracy Drill 1:
Solve all subtopic problems under timed test conditions (15 minutes).