Not sure you're on the right wavelength. The requirement is to arrive at every number up to 100. For each number, you have to use the figure 4 four times, making whatever use you like of the various mathematical symbols that the site mentions.
e.g. 16 could be 4+4+4+4 , or factorial 4 - (root 4 x root 4 x root 4), or (4x4x4) divided by 4, or root 4 x root 4 x root 4 x root 4, and probably all sorts of other variations.
4 over .4 recurring =9, so 81 could be (4 over .4 recurring) x (4 over .4 recurring)
Best of luck.