Question

From 5 liters of 20% solution of alcohol in water 2 liters of solution is taken out and 2 liters water is added to it The strength of alcohol in the new solution is

• A. 12%
• B. 15%
• C. 16%
• D. 18%

Answer 1

The correct option is A 12%

2 L of solution is removed remaining solution will be 5-2 =3L

Mount of alcohol in in 3 L solution is $\frac{20}{100}\times 3$=$\frac{3}{5}$

After adding 2 liter of water amount of solution become 5 L but with different strength.

We have 5 L of solution in which $\frac{3}{5}$ L is alcohol

% of alcohol in 5 L solution = $\frac{3}{5}$x$\frac{100}{5}$=12%

Socorrect answer will be option A