In a 140 litre of mixture of milk and water, percentage of water is only 30%. The milkman gave 20 litre of this mixture to a customer. Then he added equal quantities of pure milk and water to the remaning mixture. As a result the respective ratio of milk and water in the mixture became 2:1. What was the quantity of milk added ? (in litres)
Explanation:
Original mixture = 140 litre
After giving 20 litre of mixture to customer,
Remaining mixture = 140-20=120 litre
According to question,
Percentage of water = 30%
∴ Quantity of water = 30/100×120 = 36 litre
So, Quantity of milk = 120-36=84 litre
Let the quantity of both pure milk and water be added
= x litre
∴ 84+x/36+x = 2/1
84+x = 72+2x
x=12 litre