Answer: son is 12 years old
Step-by-step explanation:
Let m be the age of mother, f be the age of father, and s be the age of son.
m + f + s = 28 x 3 = 84
m + son = 23 x 2 = 46
f + s = 25 x 2 = 50
m = 46 - s
f = 50 - s
we plug in m and f to the functions.
we get 46 - s + 50 - s + s = 84
96 - s = 84
-s = -12
s = 12 years old
