If a chemist needs 90 milliliters of a 69% solution but only has 61% and 79% solutions available, how many milliliters of each solution should be mixed together
+128474 Let the number of milliliters of 61% solution be x
Let the number of milliliters of 79% solution be (90- x)
So
61% * number of mils of this solution + 79% * number of mils of this solution = 69% * 90
So
.61 * x + .79 (90 - x) = .69 * 90 simplify
.61x + 71.1 - .79x = 62.1
-.18x + 71.1 = 62.1 subtract 71.1 from both sides
-.18x = -9 divide both sides by -.18
x = 50
So.....50 mils of 61% solution
And
(90 -50) = 40 mils of 79% solution
