If you divide a number by 4 and multiply it by 1/4 you will obtain the same result, because "1/4" is one fourth of the number which is the same as dividing it by four. So these two operations are equal.
Example:
[tex]\begin{gathered} 100\colon4\text{ = 25} \\ 100\cdot\frac{1}{4}\text{ = 25} \end{gathered}[/tex]