Pythons has binary floating point, which does not give the same
results as a pocket calculator.

You can see the differences by using the decimal module:


# These are the binary floats in exact decimal representation.
>>> Decimal(7.95)
Decimal('7.95000000000000017763568394002504646778106689453125')
>>> Decimal(8.95)
Decimal('8.949999999999999289457264239899814128875732421875')


# This is exact decimal arithmetic.
>>> Decimal("8.95") + Decimal("0.95")
Decimal('9.90')