It will take about 15 seconds, read and do it at the same time so that you will not lose the fun.
 Take a look at your last digit of your cell phone number
 Use this figure and multiply by 2
 Then add 5
 And then multiply by 50
 And then add the number 1763
 The last step; with this number, subtract your birth year.
Now you see a three-digit number.
The first digit is the last digit of your phone number, the next digits is your actual age!