Question

Calcular o valor das expressões numéricas, lembrando a ordem das operações:
a) ( 1/4 + 2/5 ) : ( 1/3 + 1/10)=
b) 2×3 3/1 7/1 = 2+14

Answer 1

$( \frac{1}{4} + \frac{2}{5} )\div( \frac{1}{3} + \frac{1}{10} )= \\ \\ ( \frac{5+8}{20} )\div( \frac{10+3}{30} )= \\ \\ \frac{\not13}{20} \times \frac{30}{\not13} = \frac{30}{20} = \frac{3}{2} =1 \frac{1}{2}$