Ok, I got this as an email forward (I know posting fowards in the straightdope is prohibited in a unwritten law here) but I was freaked out about how this worked and was wondering (since I have the math capabilities of a chimp) if anyone can explain how this match trick works…thanx
Reoch

First of all, pick the number of times a week that you would like to have
chocolate. (Try for more than once but less than 10) 
Multiply this number by 2 (Just to be bold)

Add 5. (for Sunday)

Multiply it by 50…I’ll wait while you get the calculator…

If you have already had your birthday this year add 1752…
If you haven’t, add 1751… 
Now subtract the four digit year that you were born.
You should have a three digit number…
The first digit of this was your original number (i.e. How many times you want to have chocolate each week).
The next two numbers are…
YOUR AGE! (OH yes it is!!!)