CREATING MY OWN NUMBER SYSTEM!!!!! 10 POINTS!!!!!

Well, i'm in the midst of creating my own number system. It can be in base 3-9. I decided to use base three and i'm using A-J to represent values 0-9. Any tips on how to show/designate place value? The math in converting is a breeze im just to mentally challenged to actually create the basic system. Any and all tips are MUCH appreciated!

You can't use A-J to represent 0-9 in base 3, in base 3 you only have 0,1,2 to play with so you only need ABC.

To deal with place value you would do it the same way you do in any other counting system that has place value use a decimal point - you can choose any character you want to represent a decimal point every character to the left of the decimal point is 3 times more than the one to the left and every value to the left is 1/3 of the value, so AB.BA = 8 7/9ths as well as a Swedish pop group.

If you want to go completely against this method that we're so used to invent totally different rules, Roman numerals has no real place value per ce, the letter in front of a larger letter is subtracted, the higher value letters go first so a C would come before M if the C was to be subtracted from the M and afterwards if it was to be added but since it's your number system you can invent any arbitrary rules you like.

If a system is base 3 you only need 3 digits - 0, 1, 2

The number 3(base 10) would be represented by 10

Why would you create a number system if we already have a perfectly good one