Please, post your code in a comment with a spoiler tag. The only reason I can think of why this is happening is that you're overwriting some functions globally.

Description says:

Input
a string strng of n positive numbers (n = 0 or n >= 2)

Nothing is said about trailing spaces or not. You could have simply taken a split function without separator. Nevertheless I added such an example in "TEST".

Sorry, I missed the second part of your message. You are absolutely right that more tests are necessary to eliminate approximate solutions. Unfortunately, it is not possible to test cases like 82.999999998859% because they require very long input strings.

The problem is well-defined mathematically. Floating-point numbers are not mentioned anywhere in the description. And it is possible to solve this kata without them.

Moreover, in many real-life situations floating-point numbers cannot be used directly. Final results have to be rounded to some integer (or even boolean) values. That's the point which this kata tries to teach (at least that was my motivation when I approved this kata).

This kata is in draft state, and you cannot submit solutions to it.