|(experimental value) - (theoretical value)| / theoretical value * 100%?

Calculate the percent error in the experiment using the experimental and theoretical values of the mass percent of oxygen

INFO
Mass with 0.1 grams MNO2 = 53.300 grams + 20 g KClO3 = 73.300g, after burning so only KCl remained = 65.467 grams
Update: theoretical mass percent of oxygen = 100 x (mass of 3 oxygen atoms) / (mass of KClO₃)

I got 39%

Calculate the percent error in the experiment using the experimental and theoretical values of the mass percent of oxygen. The percent error is defined as
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