Exercicis de Valor absolut d'un nombre real

$|{\displaystyle \frac{1}{2}}-{\displaystyle \frac{2}{3}}+{\displaystyle \frac{1}{5}}|=|{\displaystyle \frac{15-20+6}{30}}|=|{\displaystyle \frac{1}{30}}|={\displaystyle \frac{1}{30}}$

$0,6={\displaystyle \frac{6}{10}}={\displaystyle \frac{3}{5}}$, i per poder comparar ambdues fraccions, fem ${\displaystyle \frac{3}{5}}={\displaystyle \frac{18}{30}}$, de manera que és fàcil veure que ${\displaystyle \frac{1}{30}}<{\displaystyle \frac{18}{30}}$

$|-0.75|=max(0.75,-0.75)=0.75$

$|{\displaystyle \frac{1}{5}}-{\displaystyle \frac{1}{3}}|=|{\displaystyle \frac{3-5}{15}}|=|{\displaystyle \frac{-2}{15}}|={\displaystyle \frac{2}{15}}$