Difficulty: Easy
Correct Answer: 15 years
Explanation:
Introduction / Context:
One person’s future age is given along with a present-time ratio. Use the future age to back out that person’s present age, then apply the ratio to compute the other person’s present age.
Given Data / Assumptions:
Concept / Approach:
From G + 6 = 26 get G = 20. Then find k = 20/4 = 5, and M = 3k.
Step-by-Step Solution:
Verification / Alternative check:
Check ratio now: 20 : 15 = 4 : 3 ✓.
Why Other Options Are Wrong:
12/17/19.5/21 years would break the 4:3 present ratio given G = 20.
Common Pitfalls:
Forgetting to subtract the 6 years to get the present age; incorrectly distributing the ratio before determining k.
Final Answer:
15 years
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