Strange result with floating point addition

Question

Why is it when I print/display the result of

eval(\"11.05\") + eval(\"-11\")

it comes out as 0.05000000000000071 instead of the expecte

Answer 1

This has nothing to do with eval. In fact, this is what happens if you type in a console 11.05 - 11:

This is a consequence of how programming languages store floating-point numbers; they include a small error. If you want to read more about this, check this out.