4) Misty wishes to obtain 85 ounces of a 40% acid solution by combining a 72% acid solution with a 25% acid solution. How much of each solution should Misty use?

Step-by-step explanation:

If x is the volume of 25% solution, and y is the volume of 72% solution, then:

x + y = 85

0.25x + 0.72y = 0.40 (85)

Solve the system of equations using substitution or elimination:

0.25x + 0.72 (85 - x) = 0.40 (85)

0.25x + 61.2 - 0.72x = 34

27.2 = 0.47x

x ≈ 57.9

y ≈ 27.1

Misty needs 57.9 ounces of 25% solution and 27.1 ounces of 72% solution.