Question

quanto é
$\frac{8}{9}$
menos
$\frac{4}{5}$
?

​

Answer 1

$\frac{8}{9} = \frac{40}{45} \\ \frac{4}{5} = \frac{36}{45 } \\ \frac{40}{45} - \frac{36}{45} = \frac{4}{45}$