Question

Kristina needs to mix a 10% alcohol solution with a 50% alcohol solution to create 200 millileters of a 48% solution. How many millileters of each solution must Kristina use?

Answer: Kristina must mix
______ millileters of 10% solution and
______ millileters of 50% solution.

Answer 1

• 10%: 10 mL
• 50%: 190 mL

Explanation:

Let v represent the volume of the 50% solution, in milliliters. Then 200-v will be the volume of 10% solution. The amount of alcohol in the mix will be ...

0.50v +0.10(200-v) = 0.48(200)

0.40v +20 = 96 . . . . . . simplify

0.40v = 76 . . . . . . . . . subtract 20

v = 190 . . . . . . . . . . . divide by 0.4

Kristina must mix ...

10 mL of 10% solution

190 mL of 50% solution