There are four people in a family. The average age of these four members is 32 years. The father's age is 50 years, the mother's age is 46 years, and the daughter's age is 20 years. Find the age of the only son in the family.

12 years

ATQ,

Sum of age of the family = 32 × 4 = 128

Given, father's age = 50 years

          mother's age = 46 years

          daughter's age = 20 years

So, age of the only son of the family = 128 - 50 - 46 - 20

                                                      = 12 years