This year, the father is 30 years older than his son, but eight years ago, the father was 30 years older than his son.

Eight years ago, my father was four times as old as my son, which means my father was three times as old as my son.

Then the age of the son in that year is: 30÷(4- 1)= 10 years old.

My son's age this year is: 10+8= 18.

Dad's age this year is: 18+30=48.

A: Son 18 years old, father 48 years old.