A restaurant owner was experimenting with the taste of her homestyle lemon drink. She started with 60 litres of water. She removed 15 litres of the water and replaced it with 15 litres of pure lemon juice. After thoroughly stirring the new mixture, she discovered that it was too “lemony”. So she removed 10 litres of the new mixture and replaced it with 10 litres of water. She thoroughly stirred the mixture and concluded that the new mixture was just right.
Determine the ratio of pure lemon juice to water in the final 60 litre mixture.