Question

Explain how to divide a over b divided by c over d

Answer 1

flip c over d to d over c and multiply it so:
$\frac{a}{b} \times \frac{d}{c}$

Answer 2

So a over b divided by c over d looks like the following

$\frac{a}{b}\div\frac{c}{d}$

In order to divide two fractions, you multiply by the reciprocal (also known as the multiplicative inverse).

The reciprocal is the fraction "flipped"

$\frac{a}{b}\div\frac{c}{d} = \frac{a}{b}\times\frac{d}{c}\\\frac{a}{b}\times\frac{d}{c} = \frac{ad}{bc}$