Convert grams —> mols and then mols —> atoms
We know that there are 6.02 x 10^23 atoms/mol
And we know that there are about 160 grams of fe2o3 per mol
So (79g fe2o3)/(160 g/mol) = .49 mol fe2o3
Now we use avogadro’s number to do
(.49 mol fe2o3)/(6.02 x 10^23 atoms/mol) = the answer.
I’ll leave the easy math to you.
