Python float division "rounding error" on division by 100

When dividing a float by 100 in Python 2.7 I get the following "rounding behaviour":

>>> 3.7e-03/100

3.7000000000000005e-05

I would expect the following:

>>> 3.7e-03/100
3.7e-05

Note that:

>>> 3.7e-03/100 == 3.7e-05
False
>>> 3.7000000000000005e-05 == 3.7e-05
False

While probably of not practical difference in most applications I find this behaviour somewhat disconcerting.

Why does this happen and how can I avoid it?

I am using Python:
'2.7.5 |Anaconda 1.7.0 (32-bit)| (default, Jul 1 2013, 12:41:55) [MSC v.1500 32 bit (Intel)]'