Four Fours/10

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Puzzle

Using exactly $4$ instances of the number $4$, the task is to write an expression for $10$, using whatever arithmetical operations you consider necessary.


Solutions

Solution $1$

$10 = 4 + 4 + 4 - \sqrt 4$

Solution $2$

$10 = 4 + 4 + \dfrac 4 {\sqrt 4}$

Solution $3$

$10 = 4 + \sqrt 4 + \sqrt 4 + \sqrt 4$

Solution $4$

$10 = \dfrac {4 \times 4 + 4} {\sqrt 4}$

Solution $5$

$10 = \paren {4 + \dfrac 4 4} \times \sqrt 4$


Also see

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