Question

Bruce wants to make 50 ml of an alcohol solution with a 12% concentration. He has a 10% alcohol solution and a 15% alcohol solution. The equation 0.10x + 0.15(50 – x) = 0.12(50) can be used to find the amount of 10% alcohol solution Bruce should use. How much of the 15% alcohol solution should Bruce use?

Answer 1

Answer:

Bruce wants to make 50 ml of an alcohol solution with a 12% concentration. He has a 10% alcohol solution and a 15% alcohol solution. The equation 0.10x + 0.15(50 – x) = 0.12(50) can be used to find the amount of 10% alcohol solution Bruce should use.

How much of the 10% alcohol solution should Bruce use?

30

mL

How much of the 15% alcohol solution should Bruce use?

20

mL

Step-by-step explanation:

Answer 2

(50 - x) is the amount of the 15% Alcohol solution to use. If you solve for x first.
0.10x + 0.15(50 – x) = 0.12(50)
0.10x - 0.15x + 7.5 = 6
-0.05x + 7.5 = 6
7.5 - 6 = 0.05x
1.5 = 0.05x
1.5/0.05 = x
30 mL = x

Then the 15% solution: 50 - 30 = 20 mL