Help with a Chemistry Mole problem please!?

Question

A mixture of Na2O and BaO that weighs 6.50 g is dissolved in water and this solution is then treated with dilute sulfuric acid (H2SO4). BaSO4 precipitates from the solution, but Na2SO4 is soluble and remains in solution. The BaSO4 is collected by filtration and, when dried, is found to weigh 7.61 g. What percentage of the original sample of mixed oxides is BaO? (FW of BaO = 153.3, BaSO4 = 233.4, Na2O = 62.0)

the answer is 76.9% but i don't even understand the question because its so wordy. any help would be amazing, thanks!

Answer 1

first question: how much BaO produced 7.61 grams of BaSO4, using molar masses:

7.61 g BaSO4 @ 153.3 g/mol BaO / 233.43 g/mol BaSO4 = 5.00 g BaO

What percentage of the original sample of mixed oxides is BaO?

5.00g BaO / 6.50 g sample  times 100 = 76.89%

your answer: 76.9% (3 sig figs)