Question 354271

10% alcohol solution must be mixed with 18 ounces of a 15% alcohol solution to make a 13% alcohol solution?
*Note: Let x be the amount of the total 10% solution.
.
.10x + .15*18oz = .13(18oz+x)

.15*18oz + .13*18oz = .13x - .10x
.
.02*18oz = .03x

12oz = x
. 
check our answer
1.2 + 2.7 = 3.9