1 litre of water is added to 5 litres of alcohol-water solution containing 40% alcohol strength. The strength of alcohol in the new solution will be :

Answer: Option D

40% = $$\frac{2\to \text{Alcohol}}{5\to \text{Mixture}}$$
Water : Alcohol
     3   :   2
Required percentage
= $$\frac{2}{(5+1)}$$ × 100
= $$\frac{2}{6}$$ × 100
= $$\frac{1}{3}$$ × 100
= $$33\frac{1}{3}$$%