What is the square root of 12/15?

$\frac{2}{5} \sqrt{5}$
$\sqrt{\frac{12}{15}} = \sqrt{\frac{4}{5}} = \sqrt{\frac{20}{25}} = \sqrt{\frac{{2}^{2} \cdot 5}{{5}^{2}}} = \frac{2}{5} \sqrt{5}$