Question 183137
Let x = quarts of 50% solution added
then
"acid from start" + "added acid" = "concentration desired"
.10(8) + .50x = .30(8+x)
.80 + .50x = 2.4 + .30x
.80 + .20x = 2.4
.20x = 1.6
x = 8 quarts