A chemist currently has a solution of 30% hydrochloric acid and a solution of 15% hydrochloric acid. He mixes the two solutions together to create 24 ounces of a 25% hydrochloric acid solution. How many ounces of the 30% hydrochloric acid solution did he use in order to obtain the 25% solution?
let amount of 30% ounces be x and that of 15% ounces by y. x+y=24....i 0.30x+0.15y=0.25(24)....ii from i: x=24-y...iii substitute iii in ii we get: 0.30(24-y)+0.15y=6 7.2-0.3y+0.15y=6 -0.15y=-1.2 y=8 ounces x=24-8=16 ounces
