Rounding Problem with Python [duplicate]

Answer 1

You are not doing anything wrong. This is due to the internal representation of the numbers:

For example, try this:

0.1 + 0.1 +  0.1 + 0.1 +  0.1 + 0.1 +  0.1 + 0.1 +  0.1 + 0.1

If you need more precision use the decimal representation