Two vessels of equal capacity, and both completely filled, contain mixtures of milk and water in the ratio of 5 : 1 and 6 : 5, respectively. Both the mixtures are now mixed thoroughly. What is the ratio of milk to water in the new mixture so obtained?

91 : 41

Solution A,

 M  :  W 

  5  :  1

Solution B,

 M  :  W

 6   :  5

⇒ Making quantity equal of both solution, we multiply Sol. A with 11 and Sol. B with 6,

⇒ (5 : 1) x 11 = 55 : 11 and     (6 : 5) x 6 = 36 : 30

⇒ Adding both the solutions, we get

⇒ (55 + 36) : (11 + 30) = 91 : 41

⇒ Milk : Water = 91 : 41