Past total and current ratio: Five years ago, the sum of father and son’s ages was 60. Currently, their age ratio is 4 : 1. What is the father’s present age?

Introduction / Context:
This blends a past-sum constraint with a present ratio. Using the present ratio to express both ages, then applying the past-sum condition (subtracting 5 from each) yields a single equation for the scale factor.

Given Data / Assumptions:

• Let present father = 4k, son = k.
• Five years ago: (4k − 5) + (k − 5) = 60.

Concept / Approach:
Set up the linear equation in k and solve, then compute 4k for the father’s age. This keeps the algebra minimal while respecting both time points.

Step-by-Step Solution:

Verification / Alternative check:
Five years ago: father 51, son 9; sum 60 as stated. Present ratio 56 : 14 reduces to 4 : 1.

Why Other Options Are Wrong:
48/51/61 do not satisfy both the past sum and the present ratio simultaneously.

Common Pitfalls:
Subtracting 5 from only one age or applying the ratio to the past instead of the present.

Final Answer:
56 years