Do you know math

To My Dear Wife,
"You will surely understand that I have certain needs that being with a
54-year old you can no longer supply. I am very happy with you and value
you as a good wife.   Therefore, after reading this fax, I hope you will not
wrongly  interpret the fact that I will be spending the evening with my 18
year old secretary at the Comfort Inn Hotel.  Please don't be perturbed I
shall be back home before midnight".

When the man came home, he found the following letter on the dining
room  table.

My Dear Husband,
I received your fax and thank you for your honesty.  I too am very
happy with you and value you as a good husband.  I would like to
take this opportunity to remind you that you are also 54 years old.
At  the same time I would like to inform you that while you read this,
I will be at the Hotel Fiesta with Michael, my tennis coach, who like
your secretary is also 18 years old.  "As a successful businessman
and with your excellent knowledge of Math, you will understand that
we are in the same situation, although with one small difference.

18 goes into 54 more often  than 54 goes into 18.

Therefore I will not be home until tomorrow afternoon

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