Ages (present multiple plus future-sum constraint): A mother is five times as old as her son. After 4 years, the sum of their ages will be 44. Find the son's present age.

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