Question

The average mother's, father's, and son's age is 28 years. The average mother's and son's age is 23 years. The average father's and son's age is 25 years. What is the son's age?

Answer 1

Answer: son is 12 years old

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