float / rounding question

[helen.m.flynn at gmail.com]

Hi I'm very much a beginner with Python.
I want to write a function to convert celcius to fahrenheit like this
one:

def celciusToFahrenheit(tc):
    tf = (9/5)*tc+32
    return tf

I want the answer correct to one decimal place, so
celciusToFahrenheit(12) would return 53.6.

Of course the function above returns 53.600000000000001.

How do I format it correctly?