It is given that a 5% alchohol solution needs to be prepared.
It is given that 60ml of 60% pure alchohol solution.
So let x ml of pure water be added, so it follows:
[tex]60(\frac{60}{100})+x(\frac{0}{100})=(60+x)\frac{5}{100}[/tex]
Solve for x to get:
[tex]\begin{gathered} 36=\frac{\mleft(60+x\mright)}{20} \\ 720=60+x \\ x=660 \end{gathered}[/tex]
660 ml of pure water needs to be added to get the 5% solution.
b) You will need 660ml of pure water to obtain 720ml of the desired 5% solution.
