Math lesson

[TonySmith]

A Professor of Mathematics sent a fax to his wife. It reads:


Dear Wife:
You must realize that you are 54 years old and that I have certain needs that you are no longer able to satisfy. I am otherwise happy with you as a wife and hope you will not be offended to learn that by the time you receive this, I will be at the Grand Hotel with my
18 year-old teaching assistant. I'll be home before midnight.
Your Husband"

When he arrives at the hotel there is a fax waiting for him on his bed. It reads:

"Dear Husband You, too, are 54 years-old, and by the time you receive this letter, I will be at the Breakwater Hotel with the 18 year-old pool boy. Being the brilliant Mathematician that you are, you can easily appreciate the fact that 18 goes into 54 a lot more times than 54 goes into 18. Don't wait up.
Your Wife.