To make it easier, assume that we have a total of 100 g of a compound. Hence, we have 58.80g of xenon, 7.166g of oxygen, and 34.04g of fluorine. Know we will convert each of these masses to moles by using the atomic masses:
58.8/131.3 = 0.45 mole of Xe 7.166/16 = 0.45 mole of O 34.04/19 = 1.79 mole of F
Now, we will divide all the mole numbers by the smallest among them and get the number of atoms in the compound:
Xe = 0.45/0.45 = 1 O = 045/0.45 = 1 F = 1.79/0.45 = 3.98 = 4
