18 is what percent of 72

Divide 18 by 72:

$${\frac{{\mathtt{18}}}{{\mathtt{72}}}} = {\frac{{\mathtt{1}}}{{\mathtt{4}}}} = {\mathtt{0.25}}$$

0.25 is the same as 25%

$$\begin{array}{lcl}
\dfrac{18}{72}&\times&\dfrac{100}{100}\\ \\
=\dfrac{18}{72}&\times&100*\dfrac{1}{100}\\\\
=\dfrac{18}{72}&\times&100*\%\\\\
=\dfrac{1800}{72}&\times& \% \\ \\
=\dfrac{1800}{72}\%\\\\
=25\%
\end{array}\\$$

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