Question

A jar full of whisky contains 40% alcohol. A part of this whisky is replaced by another containing 19% alcohol and now the percentage of alcohol was found to be 26%. What quantity of whisky is replaced ?

• A. $\frac{2}{3}$
• B. $\frac{1}{3}$
• C. $\frac{3}{7}$
• D. $\frac{4}{7}$

Answer 1

Answer: (A)

$\frac{2}{3}$

Answer 2

0$\%$ alcohol solution is mixed with 19$\%$ alcohol solution to give 26$\%$ alcohol solution.

$\frac{w1}{w2}=\frac{(A2-Aavg)}{(Aavg-A1)}$

$=\frac{(40-26)}{(26-19)}$

$=\frac{14}{7}=\frac{2}{1}$

So 2 parts of 19$\%$ solution was mixed with 1 part of 40$\%$ solution. This means that $\frac{2}{3}^{rd}$ of the 40$\%$ solution was replaced by 19$\%$ solution. So the correct option is (A)