Question

Two hundred milliliters of pure water is added to 300 milliliters of a solution which is 12% salt. What is the percentage of salt in the resulting solution?

• A. 6.0 %
• B. 6.5 %
• C. 6.9 %
• D. 7.2 %
• E. 7.5 %

Answer 1

The correct option is D 7.2 %

$300$ milliliters of a solution contains $12\%$ of salt.

$\Rightarrow$ Salt contain in $300ml$ solution $=12\%$ of $300$

$=\frac{12}{100}\times 300$

$=36ml$

$\Rightarrow$ Total solution after adding pure water $=(200+300)ml$

$=500ml$

$\Rightarrow$ $\%$ of salt in resulting solution $=(\frac{36}{500}\times 100)\%$

$=\frac{36}{5}\%$

$=7.2\%$