This is geeky, but fun too.
Firstly, pick the number of times in a week you would like to have a drink, any number you pick must be more than 1 and less than 10.
Multiply by 2, add 5 and multiply by 50 again.
If you’ve had your birthday this year already add 1762, if you haven’t, add 1761. After adding, subtract the 4 digits in the year you were born from the initial answer.
The result is a 3 digit number, the 1st number by the left is the original number you picked at the beginning while the next two digits make up your age.