You can build your own floating point number system, using an a couple of integers, one for after the decimal point and one for before. You'll need to use types to store your numbers, to put the two ints in fields. Perform each calculation on both parts of the number, then add the results into one number. That way you can work with more decimal points more accuratly and return the floating point number back as normal.
TBH, it's probably more hassle than it's worth though :/
TBH, it's probably more hassle than it's worth though :/