Titration here we go

A 1.219-g sample containing ammonium sulfate, ammonium nitrate and nonreactive substances was diluted to 200 mL in a volumetric flask. A 50.00 mL aliquot was made basic with strong alkali, and the liberated ammonia was distilled into 30.00 mL of 0.08421 M HCl. The excess HCl required 10.17 mL of 0.08802 M NaOH for neutralization.

A 25.00-mL aliquot of the sample was made alkaline after the addition of Devarda's alloy, and the nitrate ion was reduced to ammonia. The ammonia from ammonium ion and nitrate ion was then distilled into 30.00mL of the standard acid and back-titrated with 14.16mL of the base.

Calculate the percentage of ammonium nitrate in the sample.

Your answer should be reported with 3 significant figures.