Four vessels of equal size are filled with mixtures of milk and water. The strength of milk in the four vessels are 80%, 75%, 60% and 50% respectively. If all four mixtures are mixed together then what is the ratio of milk to water in the resultant mixture?

53 : 27

Ratio of milk to water in first vessel = 80 : 20   ----(1)

Ratio of milk to water in second vessel = 75 : 25    ----(2)

Ratio of milk to water in third vessel = 60 : 40   ----(3)

Ratio of milk to water in fourth vessel = 50 : 50   ----(4)

Note:Here the sum of ratio of milk and water in all vessels are equal i.e.100. Therefore, in this condition we can directly add all four ratio of milk and water individually.

Now, add all the ratio of milk and water in fifth vessel:

Ratio of milk to water in fifth vessel =

(80 + 75 + 60 + 50) : (20 + 25 + 40 + 50) = 265 : 135  = 53 : 27

Ratio of milk to water in fight vessel = 53 : 27