Question

A sample of nicotine weighing 0.3204 g was vaporized in a flask with a volume of 487 mL. This sample exrted pressure of 74.3 mm Hg at 20 degrees C. What is the molar mass of nicotine?

I know this has to do with N=P*V/R*T. and 1 atm=760 mm Hg.
Please help and show work. chemistry is not a good subject for me and i'm struggling to understand. thanks