Difficulty: Medium
Correct Answer: 35 years
Explanation:
Introduction / Context:
The mix of a fixed present difference and a past multiplicative relationship yields a single linear equation. Solve using a present variable and a time shift to the past.
Given Data / Assumptions:
Concept / Approach:
Set (x + 25 − 5) = 6(x − 5) and solve for x; then compute the mother’s current age.
Step-by-Step Solution:
1) x + 20 = 6x − 30.2) 50 = 5x ⇒ x = 10.3) Mother now = x + 25 = 35 years.
Verification / Alternative check:
Five years ago: daughter = 5, mother = 30; indeed, 30 = 6 × 5. The data are consistent.
Why Other Options Are Wrong:
Common Pitfalls:
Forgetting to subtract 5 from both ages or mixing up whose age is a multiple of whose can lead to errors.
Final Answer:
35 years
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