A jug holds 20 litres of pure juice. 5 litres are poured out and replaced with water, and then 5 litres of the mixture are poured out and replaced with water. What percentage of the jug is now juice?

Explanation

1. 01

   Each time $\frac{5}{20} = \frac{1}{4}$ of the contents go, so $\frac{3}{4}$ of the juice stays.

2. 02

   After two times, $\left(\frac{3}{4}\right)^{2} = \frac{9}{16} = 56.25\%$ is juice.