Question

X liters of milk is taken out and replaced with water from a container having 240 liters milk. Now, 20% of the mixture is taken out and replaced with water. In final mixture, the difference in quantity of milk & water is 128 liters. Find x.

Answer 1

The value of X is equal to 10 litres.

• After replacing x litres of milk with water, the mixture contains x litres of water and 240-x litres of milk.
• When 20% of the mixture is replaced with water amount of milk replaced with water is equal to 20% of (240-x) = (240-x)/5 litres.
• Resulting amount of water in misture is equal to x+(240-x)/5 = (240+4x)/5
• Resulting amount of milk in mixture is equal to (240-x)-(240-x)/5 = 4*(240-x)/5.
• Difference between milk and water is equal to (720-8x)/5 = 128

                                                                                  ⇒8x = 720-640 = 80

                                                                                  ⇒x = 10 litres.