Think of a number

Today the language focus was on using numbers in English. We did a number puzzle. Here's another one.

1) Write down the number of the month you were born


2) Multiply it by 4

3) Add 13

4) Multiply the result by 25

5) Subtract 200

6) Add the day of the month on which you were born

7) Multiply by 2

8) Subtract 40

9) Multiply the result by 50

10) Add the last two digits of the year of your birth

11) Finally, subtract 10,500

IF THE RESULT ISN'T YOUR BIRTHDAY, TRY AGAIN!