How many moles are in a 12.0 g sample of fe2o3?

We know that Fe2O3 has a molar mass of 159.69 g / mol, therefore the number of moles of a 12 g sample is:

number of moles = 12 g / (159.69 g / mol)

number of moles = 0.075 mol

thats how its supposed to be