Question

How many ml of water must be added to $48ml$ of alcohol to make a solution that contains $25\%$ alcohol?

• A. $48$
• B. $64$
• C. $144$
• D. $192$

Answer 1

Answer: (C)

$144$

Let us suppose that we add $x$ ml of water to make the required solution.

Then, $25\%$ of $(48+x)=48$

$\Rightarrow \frac{25}{100}$ of $(48+x)=48$

$\Rightarrow \frac{25\times (48+x)}{100}=48$

$\Rightarrow 48+x=48\times 4$

$\Rightarrow x=192-43=144ml.$