A man bought milk and mixed it with water. If the mixed milk is sold at cost price and the profit is 20%, then how much water was in each liter of mixed milk?
1
\(\frac{1}{8}\) liter
2
\(\frac{1}{6}\) liter
3
\(\frac{1}{5}\) liter
4
\(\frac{1}{20}\) liter