Detailed Solution : The volume of milk in the mixture initially = (3/5) × 60 = 36 litres ⇒ Volume of water in the mixture initially = (2/5) × 60 = 24 litres Let x litres water should be added, ⇒
36
24+x
=
1
1
⇒ 24 + x = 36 ⇒ x = 12 litres ∴ 12 litres water should be added.