One man adds 3 liters of water to 12 liters of milk and another 4 liters of water to 10 liters of milk. What is the ratio of the strengths of milk in 2 mixtures?  Choose the correct answer:
A) 11:21  B) 15:33  C) 28:25  D) 3:2  E) 31:33
Strength of milk in the mixture = Quantity of milk/total quantity of mixture   strength of milk in the 1st mixture = 12/15   strength of the milk 2nd mixture = 10/14   The ratio of their strengths = 12/15 : 10/14 = 28:25   Answer is 28:25
<result>C</result>
One man adds 3 liters of water to 12 liters of milk and another 4 liters of water to 10 liters of milk. What is the ratio of the strengths of milk in 2 mixtures?