Four Fours/Lemmata/Three Fours/54/Solutions/1

Puzzle: Three Fours: $54$

Using exactly $3$ instances of the number $4$, the task is to write an expression for $54$, using whatever arithmetical operations you consider necessary.

Solution

$54 = \dfrac {\paren {\sqrt 4 + \sqrt 4 }!} {. \dot 4}$