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?

27.13 ounces of one solution and 57.87 ounce of other solution

Step-by-step explanation:

Considering 'x' no. of ounces of one solution and 'y' no. of ounces of other solution.

Lets form the equations according to the given data.

-> she wishes to obtain 85 ounces by combining both solutions

x+y= 85

x = 85- y -->eq(1)

-> by combining a 72% acid solution with a 25% acid solution  

0.72x + 0.25 y = 0.4 x 85 --> eq(2)

Substituting value of eq(1) in eq(2)

0.72(85-y) + 0.25 y = 34

61.2 - 0.72y + 0.25y = 34

-0.47y= 34-61.2

y= 27.2/0.47

y= 57.87 ounces

Plugging in eq(1)

eq(1)=> x = 85- 57.87

x= 27.13 ounces

Therefore, Misty should use 27.13 ounces of one solution and 57.87 ounce of other solution