Floating point representation

Question

https://code.sololearn.com/c2B6a34Mnox0/?ref=app

Please tell me the reason for why there is 1 in the last bit
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Answer 1

It's because of how they're stored in binary. The relevant repeating binary approximation stored leads to this.

For example, 1/10 is represented by:
0.0001100110011001100110011001100110011001100110011...

Terminate this at any value, and you get an imprecise value when converted back to decimal.