I believe this is a theoretical yield problem, so you have to convert the oxygen to moles and then convert moles of oxygen into moles of carbon dioxide. I was not sure if you needed moles or grams for the answer, so I did both (in bold).
83.42 g O2 x (1 mol / 31.99g) = 2.61g O2
2.61 g O2 x (5 mol CO2 / 8 mol O2) = 1.63 mol CO2
1.63 mol CO2 x (44.01g / 1 mol) = 71.74g CO2