Question

quanto se deve subtrair de 3/4 para obter metade de 5/7?

Answer 1

$\frac{3}{4}-x=\frac{\frac{5}{7}}{2}\\\\\frac{3}{4}-x=\frac{5}{7}\div2\\\\\frac{3}{4}-x=\frac{5}{7}\cdot\frac{1}{2}\\\\\frac{3}{4}-x=\frac{5}{14}\\\\\frac{3}{4}-\frac{5}{14}=x\\\\x=\frac{3}{4/7}-\frac{5}{14/2}\\\\x=\frac{21-10}{28}\\\\\boxed{x=\frac{11}{28}}$