Question

When water freezes its volume increases by 4%. What volume of water is required to make 221 cm³ of ice?

Answer 1

Suppose the volume of water required is x cm³.
Now, according to the question when water freezes , its volume increases by 4%, so we have

Volume of cube for x cm³ of water $=x+\frac{4}{100}\times x$
$=x+\frac{1}{25}\times x$
$=\frac{26x}{25}$

Now, given volume of ice cube =221cm³

$$\begin{gathered} \Rightarrow \frac{26x}{25}=221 \\ \Rightarrow x=221\times \frac{25}{26} \\ \Rightarrow x=212.5 \end{gathered}$$

Therefore, the volume of water required is 212.5 cm³