Answer
$\frac{3}{8y}$
Work Step by Step
To write the fraction in its simplest form, find the greatest common factor of the numerator and denominator.
$ \frac{90}{240y}= \frac{30 (3)}{30 (8y)}$
Cancel out the greatest common factor
$ \frac{30 (3)}{30 (8y)}= \frac{3}{8y}$