Difficulty: Medium
Correct Answer: 50 yr
Explanation:
Introduction / Context:Chained ratios allow writing each person’s age in terms of a single variable. A given total then determines exact values.
Given Data / Assumptions:
Concept / Approach:Let daughter = d. Then Raman = 3d; mother = (13/9) * 3d = (13/3)d. Sum and solve for d; compute mother − daughter.
Step-by-Step Solution:
Total = 3d + d + (13/3)d = (25/3)d = 125 ⇒ d = 15.Raman = 45; mother = (13/3)*15 = 65.Difference (mother − daughter) = 65 − 15 = 50.Verification / Alternative check:
Sum check: 45 + 15 + 65 = 125 ✓Why Other Options Are Wrong:
Common Pitfalls:
Final Answer:50 yr
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