How many grams of O2 are needed to completely burn 51.6 g of C3H8?

The balanced chemical equation for the combustion of propane (C3H8) is 1 C3H8 + 5 O2 -> 3 CO2 + 4 H2O. This means 5 moles of O2 are required for every 1 mole of C3H8. Calculate the moles of C3H8 in 51.6 g, then use the mole ratio to find the moles of O2 needed. Finally, convert the moles of O2 to grams.