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Nick Evershed
6,429 Points0.1 + 0.1 + 0.1 - 0.3
Im very confused how this dosent equal 0 like it would in normal math
2 Answers
Jennifer Nordell
Treehouse TeacherHi, Nick Evershed! This is true in many different programming languages. The key thing to understand here is that computers don't deal in base 10. They deal in binary. So everything you put in must first be converted to binary then do the arithmetic, then converted back to base 10.
In this process, there is often what is known as a "floating point error". There will always be a small discrepancy when doing these translations back and forth. They can be mitigated somewhat, but not eliminated.
Here's a thorough article on the matter. However, it's a bit tough to read. The main point is that shifting back and forth between base 10 and base 2 creates small discrepancies.
Hope this helps!
Christian Beckett
11,123 PointsRemember My Friend!! python is not a calculator. it can make mistakes. Nick Evershed