Question

Calcular o valor das expressões numéricas, lembrando a ordem das operações:
a) 2/3 : 4/5 + 1/2=
b) 9/5 - 7/10 : 7/5=

Answer 1

$\frac{2}{3} \div \frac{4}{5} + \frac{1}{2} = \\ \\ \frac{\not2}{3} \times \frac{5}{\not4_2} + \frac{1}{2} = \\ \\ \frac{5}{6} + \frac{1}{2} = \\ \\ \frac{5+3}{6} = \frac{8}{6} = \frac{4}{3} =1 \frac{1}{3} \\ \\ \\ b) \\ \frac{9}{5} - \frac{7}{10} \div \frac{7}{5} = \\ \\ \frac{9}{5} - \frac{\not7}{\not10_2} \times \frac{\not5}{\not7} = \\ \\ \frac{9}{5} - \frac{1}{2} = \\ \\ \frac{18-5}{10} = \frac{13}{10} =1 \frac{3}{10}$