Iron ores contain iron oxide minerals, which often contain ferric and ferrous ions. Such an ore can be analyzed for its iron content by dissolving it in acidic solution, reducing all the iron to ferrous ions, and then titrating with a standard solution of potassium permanganate. In the resulting solution, permanganate ion is reduced to manganese (II) ion, and ferrous ion is oxidized to ferric ion. A sample of iron ore weighed 0.3500 g. The titration required 41.56 mL of the permanganate solution (1.621 x 10-2 M) to reach the light purple end point. Determine the mass percent of iron in the iron ore.