Difficulty: Easy
Correct Answer: 45, 95
Explanation:
Introduction / Context:
Two linear relations are provided: a present-time difference and a future-time sum. Solving them together cleanly yields the present ages without trial-and-error.
Given Data / Assumptions:
Concept / Approach:
Solve the simple system: x + g = 140 and g − x = 50. Adding gives 2g = 190 ⇒ g = 95, then x = 45.
Step-by-Step Solution:
x + g = 140.g − x = 50.Add: 2g = 190 ⇒ g = 95.Then x = 140 − 95 = 45.
Verification / Alternative check:
Six years later: 51 + 101 = 152, as required; difference now: 95 − 45 = 50.
Why Other Options Are Wrong:
The other pairs do not simultaneously satisfy both equations.
Common Pitfalls:
Subtracting the equations in the wrong order or misreading “after 6 years” as “in 6 years total.”
Final Answer:
45, 95
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