Fractions Formulas and Notes

\displaystyle a \left( \frac{b}{c} \right) = \frac{ab}{c}

\displaystyle \frac{a}{b} + \frac{c}{b} = \frac{a+c}{b}

\displaystyle \frac{a}{b} - \frac{c}{b} = \frac{a-c}{b}

\displaystyle \frac{a}{b} + \frac{c}{d} = \frac{ad + bc}{bd}

\displaystyle \frac{a}{b} - \frac{c}{d} = \frac{ad - bc}{bd}

\displaystyle \frac{a}{b} \times \frac{c}{d} = \frac{ac}{bd}

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