Question

Express $\frac{-48}{60}$ as a rational number with denominator 5.

Answer 1

If $\frac{a}{b}$ is a rational integer and $m$ is a common divisor of $a\mathrm{and}b$, then $\frac{a}{b}=\frac{a÷m}{b÷m}$.

∴​ $\frac{-48}{60}=\frac{-48÷12}{60÷12}=\frac{-4}{5}$