Solution P is 20 percent lemonade and 80 percent carbonated water by volume; solution Q is 45 percent lemonade and 55 percent carbonated water by volume. If a mixture of PQ contains 72% percent carbonated water, what percent of the volume of the mixture is P?
Choose one
A) 48%  B) 54%  C) 60%  D) 64%  E) 68%
72% is 8%-points below 80% and 17%-points above 55%.   So the ratio of solution P to solution Q is 17:8.   Mixture P is 17/25 = 68% of the volume of mixture PQ.   The answer is 68%.
<result>E</result>
Solution P is 20 percent lemonade and 80 percent carbonated water by volume; solution Q is 45 percent lemonade and 55 percent carbonated water by volume. If a mixture of PQ contains 72% percent carbonated water, what percent of the volume of the mixture is P?