Four Fours/66

Puzzle

Using exactly $4$ instances of the number $4$, the task is to write an expression for $66$, using whatever arithmetical operations you consider necessary.

Solutions

Solution $1$

$66 = \dfrac {4!} {.4} + \dfrac {4!} 4$

Solution $2$

$66 = \dfrac {4!} {.4} + \dfrac 4 {\sqrt {. \dot 4} }$

Solution $3$

$66 = 4 \times 4 \times 4 + \sqrt 4$

Solution $4$

$66 = \dfrac {4!} {.4} + 4 + \sqrt 4$

Also see

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