The attached diagram shows the QUANTITIES and concentrations of each container. The first container has x liters in it ("how many liters of 10%..."). The second container has 30 liters (and 50% of that is acid). The third container has x + 30 liters (because you dumped the first two containers into the third container), and 20% of that is acid.
Write an equation that shows how the acid adds up:
10% of x plus 50% of 30 equals 20% of (x + 30).
You should add 90 liters of the 10% solution.
Write an equation that shows how the acid adds up:
10% of x plus 50% of 30 equals 20% of (x + 30).
You should add 90 liters of the 10% solution.
