How do you solve 5/8 -2/5 =1/y ?

$\frac{5}{8} - \frac{2}{5} = \frac{1}{y}$
$\frac{25 - 16}{40} = \frac{1}{y}$
$\frac{9}{40} = \frac{1}{y}$
color(purple)(y = 40/9