The sum of ages of a father and son is 45 years. Five years ago the product of their ages was four times the father's age at that time. The twice the difference, of father and son's age is:

The sum of ages of a father and son is 45 years. Five years ago the pr

1.	The sum of ages of a father and son is 45 years. Five years ago the product of their ages was four times the father's age at that time. The twice the difference, of father and son's age is:
A.	72
B.	45
C.	90
D.	54
Answer» E.