there are a lot of such "tricks" which you could implement and then you will have more levels.
Pick a number, any number, double the number, add 5 ,ultiply it by 50
If you have already had your birthday this year add 1759. If you haven't, add 1758, Subtract the 4 digit year that you were born.
last 2 number will be your age and the first is the initial number you have picked.
But there are like thousands of these "tricks" around.
probably its only from 1 to 10 because people can't calculate with bigger numbers in head :)
you could read my mind with the rating also.
get a number from 1-5 and substract 5 from it
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