A pharmacist has a 10% alcohol solution and a 25% alcohol solution. How many milliliters of each solution will she need in order to have 200 mL of a 20% alcohol solution?

Assuming the volume of the alcohol solution is addable, and x ml 10% alcohol solution is needed,

Then

10% x + 25% (200-x) = 20% * 200

10x + 25 *200-25x=20*200

15x=25*200-20*200=5*200=1000

x=67ml

So 67ml 10% alcohol solution is needed, and 200-67=133ml 25% alcohol solution is needed.

Secure Information

Content will be erased after question is completed.

Enter the email address associated with your account, and we will email you a link to reset your password.

Forgot your password?

Sign Up