Question

One type of liquid contains 20% water and the second type of liquid contains 35% of water. A glass is filled with 10 parts of first liquid and 4 parts of second liquid. The percentage of water in the new mixture in the glass is

• A. 20 %
• B. $24\frac{2}{7}$ %
• C. 37 %
• D. 40 %

Answer 1

The correct option is B $24\frac{2}{7}$ %

Amount of water in 10 parts of 1st liquid $=10\times \frac{20}{100}=2parts$
Amount of water in 4 parts of 2nd liquid $=4\times \frac{35}{100}=\frac{7}{5}parts$
Total water $=(2+\frac{7}{5})=\frac{17}{5}parts$
Total liquid $=10+4=14Parts$
Hence , percentage of water $=\frac{\frac{17}{5}}{14}\times 100$
$\Rightarrow \frac{17}{5}\times \frac{1}{14}\times 100=\frac{170}{7}=24\frac{2}{7}$ %