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## 'Chocolate Maths' printed from http://nrich.maths.org/

This is cool chocolate maths!!!

- First of all, pick the number of times a week that you eat
chocolate. This number must be more than one but less than
ten.
- Multiply this number by 2 (just to be bold).
- Add 5 (for Sunday).
- Multiply it by 50.
- Add 1750.
- Add the last two digits from the year you last had a birthday.
So if your last birthday was in 2009, add 9, if the your last
birthday was in 2011 then add 11.
- Now subtract the four digit year that you were born (if you
remember).

You should now have a three digit number. The first digit will
be your original number (i.e. how many times you eat chocolate each
week). The next two digits give your age. Can you explain why it
works?