Two vessels contain milk and water in the ratio of 7 : 8 and 13 : 5.  If both vessels are mixed in the ratio of 2 : 1.  Find the ratio of milk and water in new mixture.

149 : 121

          M    :    W

I   →   7    :     8   →   15  )× 6 × 2

II  →  13   :     5   →   18  )× 5 × 1

We multiplied  both ratios with 6 and 5 for making quantity equal and with 2 and 1 for asked quantity.

So,     M    :    W

         84   :    96

         65   :    25    

      149   :    121