The ratio of Acid and Water in a mixture of 25 liters is 4 : 1.  3 liters water is added to the mixture. What will be the ratio of acid and water if further 9 liters of acid is also added?

29 : 8

Total = 25 liters

Acid + Water = 4x + 1x = 5x and 5x = 25

Therefore,

Acid = 4x = 20

Water = x = 5

                                              Acid                   Water

                                           20 liters               5 liters

On adding 3 liter water            +9                     +3

& 9 liter acid                                                               

                                           29 liters               8 liters

⇒ Acid  : Water = 29  :  8