A 0.3146g sample of a mixture of NaCl(s) and KBr(s) was dissolved in water. The resulting solution required 49.60mL of 0.08765M AgNO₃(aq) to precipitate the Cl⁻(aq) and Br⁻(aq) as AgCl(s) and AgBr(s).Calculate the mass percentage of NaCl(s) in the mixture