Answer
The multiplication shortcut is simply dividing a numerator and a denominator by their common factor. Example:
$\frac{3}{5} \cdot \frac{35}{7} = \frac{3}{1} \cdot \frac{7}{7}$.
Here we divided the numerator $35$ and the denominator $5$ by their common factor $5$.
Next, we divide the numerator $7$ and the denominator $7$ by their common factor $7$:
$\frac{3}{1} \cdot \frac{7}{7} = \frac{3}{1} \cdot \frac{1}{1}$.
There is further simplification possible, so the answer is $\frac{3}{5} \cdot \frac{35}{7} = \frac{3}{1} \cdot \frac{7}{7} = \frac{3}{1} \cdot \frac{1}{1} = 3$.
Work Step by Step
Keep in mind that the answer is always in lowest term.
