Answer
To divide one fraction by another, switch the numerator and denominator of one of the fractions and multiply the two together. Then simplify if possible.
Work Step by Step
For example:
$\frac{3}{7} \div \frac{4}{5}$
Swap the numerator and denominator of one of the fractions (so $\frac{4}{5}$ becomes $\frac{5}{4}$) then multiply the fractions together
$\frac{3}{7} \times \frac{5}{4} = \frac{15}{28}$