Clodovando's father and grandfather
If x represents the last two digits of the year in which the father was born, then x + x = 38, because the statement says that the last two digits were their ages at 19.38. Solving the equation:
x + x = 38
2x = 38
x = 19
Soon, the father was born in 1919 and had 19 years in 1938.
If the father was born in 1919, the grandfather could only have been born in the previous century (18XX). Let's consider y as these last two digits. So y + y = 138 (for we are considering the previous century).
y + y = 138
2y = 138
y = 69
The grandfather was born in 1869 and had 69 1938. To find the answer to the problem, simply subtract:
69 - 19 = 50
answer: When the father was born, the grandfather was 50 years old.
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