what is negative 2/3 minus 4

or just 

$$-4\frac{2}{3}$$

$${\mathtt{\,-\,}}{\frac{{\mathtt{2}}}{{\mathtt{3}}}}{\mathtt{\,-\,}}{\mathtt{4}} = {\mathtt{\,-\,}}{\frac{{\mathtt{14}}}{{\mathtt{3}}}} = -{\mathtt{4.666\: \!666\: \!666\: \!666\: \!666\: \!7}}$$

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