Answer:
28
Step-by-step explanation:
A man is now 3 times as old as his son.
m = 3s
In 10 years time, the sum of their ages will be 76
(m + 10) + (s + 10) = 76
Subsitute for m = 3s
(3s + 10) + (s + 10) = 76
4s + 20 = 76
4s = 56
s = 14
m = 3s = 14 * 3
m = 42
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How old was the man when his son was born?
m - s = 42 - 14
m - s = 28
