Question

Efetue as operações e apresente a resposta de forma simplificada : [3\4-1\2]+3\20

Answer 1

$\left(\dfrac{3}{4}-\dfrac{1}{2}\right)+\dfrac{3}{20}\\ \\ \\ \left(\dfrac{3\cdot 1-1\cdot 2}{4}\right)+\dfrac{3}{20}\\ \\ \\ \left(\dfrac{3-2}{4}\right)+\dfrac{3}{20}\\ \\ \\ \dfrac{1}{4}+\dfrac{3}{20}=\ \dfrac{1\cdot 5+3\cdot 1}{20}=\ \dfrac{5+3}{20}=\ \dfrac{8}{20}=\ \dfrac{2}{5}$