[watchin]

You start with visualizing something like this:

Her ............Her/Him ........... Him

Since his age "now" is double that of hers "then", and the difference between "then" and "now" is the same as the diffence in their ages ...

He is twice as old as "double the difference in their ages", or four times as old as "the difference in their ages."

The difference in their ages must be an even number, in order for the sum of their ages to add up to the even number 98.

[Citizen of the Savage Nation]

Ah, hell, I just went ahead and solved it mathematically. You are correct, his age is 56 and hers is 42. The difference is 14 which is 1/4 of his age and 1/3 of hers.