Answer
$\frac{8}{9}$ .
Work Step by Step
8 days to 9 days
The ratio is $\frac{8 days}{9 days}$. Divide out the common units.
$\frac{8}{9}$ is in lowest terms
So, the ratio of 8 days to 9 days is 8 to 9 or, written as a fraction, $\frac{8}{9}$ .