Difficulty: Easy
Correct Answer: 11 : 4
Explanation:
Introduction / Context:Classic age problems often provide a ratio and the product (or sum). Use the ratio to write ages in terms of a variable, solve from the product, and then apply the time shift to compute the new ratio.
Given Data / Assumptions:
Concept / Approach:Solve x from the product, then add 5 years to each age and simplify the resulting ratio.
Step-by-Step Solution:
4x^2 = 196 ⇒ x^2 = 49 ⇒ x = 7 (ages positive).Father = 28, Son = 7.After 5 years: 33 and 12 ⇒ ratio = 33 : 12 = 11 : 4.Verification / Alternative check:Product check: 28×7 = 196; post-increment ratio simplifies correctly.
Why Other Options Are Wrong:3:1, 10:3, or 14:5 do not match the computed post-increment ages.
Common Pitfalls:Using 196 as the sum instead of product, or forgetting to simplify the final ratio.
Final Answer:11 : 4
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