Question

In a family the average age of father and mother is 40 and the average age of father, mother and son is 30. Find the age of son 

Answer 1

Answer:

10

Step-by-step explanation:

let average age of .father and mother,

now

x+y÷2=40,

x+y=80.

now,

the average age of father,mother and son,

x+y+son÷3 =30,

x+y+son=90, (x+y=80)

we know that

80+son=90

son=90_80

son age=10