Difficulty: Easy
Correct Answer: 6 years
Explanation:
Introduction / Context:
Combining a present-time multiplicative relation with a future-time sum creates a compact system solvable in one or two steps. Ensure both people advance by the same 4 years in the future constraint.
Given Data / Assumptions:
Let son's present age be s; mother's present age is 5s. After 4 years, (s + 4) + (5s + 4) = 44.
Concept / Approach:
Translate the future sum into a present equation in s and solve directly. The linearity of age changes keeps algebra simple.
Step-by-Step Solution:
Verification / Alternative check:
Mother is 30 now. In four years: 10 and 34 ⇒ sum 44 (✓).
Why Other Options Are Wrong:
Plugging them into 6s + 8 = 44 yields sums different from 44.
Common Pitfalls:
Forgetting to advance both ages by +4, or misreading “five times older” for “five years older.”
Final Answer:
6 years
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