Question

Calcular o valor das expressões numéricas, lembrando a ordem das operações:
a) (1 - 1/6)×9/5 - 1/5=
b) (2 1/2)- (3/2-1) : (1/2) + 3/4=

Answer 1

$(1- \frac{1}{6} )\times \frac{9}{5} - \frac{1}{5} = \\ \\ ( \frac{6-1}{6} )\times \frac{9}{5} - \frac{1}{5} = \\ \\ \frac{\not5}{\not6_2} \times \frac{\not9^3}{\not5} - \frac{1}{5} = \\ \\ \frac{3}{2} - \frac{1}{5} = \\ \\ \frac{15-2}{10} = \frac{13}{10} =1 \frac{3}{10} \\ \\ \\ b) \\ \frac{5}{2} -( \frac{3-2}{2} )\div( \frac{1}{2} )+ \frac{3}{4} = \\ \\ \frac{5}{2} -( \frac{1}{\not2})\times( \frac{\not2}{1} )+ \frac{3}{4} = \\ \\ \frac{5}{2} -1+ \frac{3}{4} =$
$\frac{10-4+3}{4} = \frac{13-4}{4} = \frac{9}{4} =2 \frac{1}{4}$