So when the son is 52, his dad will be 126-52 = 74 years old. Therefore, they are 74-52 = 22 years apart. And since currently the dad is 52, the son must be 52-22 = 30 years old.
When the son will be as old as father is today, their ages well add up to 126. If the present age of father is 52 years, find the present age of son?