Apharmacist has a 10% alcohol solution and a 25% alcohol solution. how many milliliters of each solution will she need to mix together in order to have 200 ml of a 20% alcohol solution?

x = volume of 10% solution to use in the mixture

y = volume of 25% solution to use

She wants a 200 mL solution, so x + y = 200.

The first solution contributes 0.10x mL of alcohol, while the second contributes 0.25y mL. Together, they make a solution with 0.20(x + y) = 0.20(200) = 40 mL of alcohol.

38.5

step-by-step explanation:

lets say, first number = r

second number = 3r+7

total = 49

(r)+(3r+7)= 49

4r+7 = 49

4r = 42

r = 42/4

r= 10.5

3r+7 = 3(10.5)+7 = 38.5

hope this

answer: the answer is 35%