Question 836291
Doreen is a chemist.  She needs to prepare 36 ounces of a 13% hydrochloric acid solution. find the amount of 18% solution and amount of 9% solution she should mix to get the solution.
.
Let x = amount (ounces) of 18% solution
then
36-x = amount (ounces) of 9% solution
.
.18x + .09(36-x) = .13(36)
.18x + 3.24-.09x = 4.68
.09x + 3.24 = 4.68
.09x = 1.44
x = 16 ounces of 18% solution
.
amount of 9% solution:
36-x = 36-18 = 18 ounces