two quarts containing 2 ⁄ 3 water and 1 ⁄ 3 formula are mixed with 3 quarts containing 3 ⁄ 8 water and 5 ⁄ 8 formula . approximately what percent of the combined 5 - quart mixture is water ?  Answers.
A) 40 %	B) 45 %	C) 50 %	D) 55 %	E) 60 %

Rationale: since we are asking of water in the end , lets concentrate on water only . . a solution has 2 quarts with fraction of water = 2 / 3 , almost 67 % . . b solution has 3 quarts with fraction of water = 3 / 8 almost 37 % . . so the ratio a : b = 2 : 3 . . . the average will therefore be closer to b % and will be 2 / ( 2 + 3 ) of { 67 - 37 } away from b . . 2 / ( 2 + 3 ) of { 67 - 37 } = 2 / 5 * 30 = 12 . . so 37 + 12 = 49 nearly 50 % answer : c
Answer: C