Question

40 litres of a mixture of milk and water contains 10% water. The water to be added to make the water content 20% of the new mixture is:

• A. 6 litres
• B. 6.5 litres
• C. 5.5 litres
• D. 5 litres
• E. None of the above

Answer 1

The correct option is D 5 litres

Amount of milk and water in the mixture is 36 litres and 4 litres, respectively.
Now, let x litres of water be added
20% of (40+x)=4 +x
or, 40+x=20+5x
or, 4x=20 or, x =5 litres.