A 54 year old accountant leaves a letter for his wife one Friday evening that reads...

Dear Wife,
I am 54 and by the time you receive this letter I will be at the Grand Hotel with my beautiful and sexy 18 year old secretary.

When he arrived at the hotel there was a letter waiting for him that read as follows...

Dear Husband,
I too am 54 and by the time you receive this letter I will be at the Breakwater Hotel with my handsome and virile 18 year old boy toy. You, being an accountant, will appreciate that 18 goes into 54 many more times than 54 goes into 18."