you only have single precision to work with in classic afaik, you could write a "longhand" routine to work with the numbers as strings (write a program to do the math as you would do on a piece of paper) that would allow you any precision you wanted.
Naturaly it would not be as fast as the internal math routines and don`t expect a snippet since math was never my strong point, subtraction would be something like padding the two strings to be the same length, subtracting them together a number at a time from the lowest value upwards, placing the result in a new string number by number, then when the code ends then just display the new number.
You would have to make functions for multiply, add and subtract in this case, I would make the subtract function first and then try the multiply function, for multiply you need to do several multiplies (for each number in the multiplier), then use the add function to add them together, slow and tedious to code, but it would make it possible to calculate to any precision you wanted.
Mentor.
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