A lab technician mixed a 660 ml. solution of water and alcohol. If 3% of the soulution is alcohol how many milliliters of alcohol were used, and how many milliliters of water were used?

Solution:

Alcohol: x

So the equation is

3%*660 ml = x

x = 19.8

660 ml -19.8 ml = 640.2 ml

So 19.8 ml of alcohol were used and 640.2 ml of water were used