#### Answer

$1\frac{1}{6}$

#### Work Step by Step

When $y=\frac{2}{5}$ and $z=\frac{5}{6}$:
$5y-z$
$=(5\times\frac{2}{5})-(\frac{5}{6})$
$=\frac{5}{1}\times\frac{2}{5}-\frac{5}{6}$
$=\frac{1}{1}\times\frac{2}{1}-\frac{5}{6}$
$=2-\frac{5}{6}$
$=\frac{12}{6}-\frac{5}{6}$
$=\frac{7}{6}$
$=1\frac{1}{6}$