Four Fours/53/Solutions/2

Puzzle: Four Fours: $53$

Using exactly $4$ instances of the number $4$, the task is to write an expression for $53$, using whatever arithmetical operations you consider necessary.

Solution

$53 = \dfrac {4! - \sqrt 4} {.4} - \sqrt 4$

Sources

• 1980: Angela Dunn: Mathematical Bafflers (revised ed.) ... (previous) ... (next): $1$. Say it with Letters: Algebraic Amusements: Four Fours