Question

Multiply:

$\frac{-3}{7}$ by $\frac{-7}{3}$

Answer 1

We know, $\mathrm{Product}\mathrm{of}\mathrm{two}\mathrm{rational}\mathrm{numbers}=\frac{\mathrm{Product}\mathrm{of}\mathrm{their}\mathrm{numerators}}{\mathrm{Product}\mathrm{of}\mathrm{their}\mathrm{denominators}}$

So, $\frac{-3}{7}$ by $\frac{-7}{3}$

$$\begin{gathered} =\frac{-3}{7}\times \frac{-7}{3} \\ =\frac{-3\times -7}{7\times 3} \\ =\frac{-\cancel{3}\times -\cancel{7}}{\cancel{7}\times \cancel{3}} \\ =\frac{-1\times -1}{1} \\ =1 \end{gathered}$$

Hence, $\frac{-3}{7}$ by $\frac{-7}{3}$ is $1$.