Question

A expressão (1/2 + 1/3 ) -¹ + 2/3   é igual a :

a)1/4   b) 28/15   c) 13/15    d) - 12/5

Answer 1

$( \frac{1}{2} + \frac{1}{3} ) ^{-1} + \frac{2}{3}$

$( \frac{3}{6}+ \frac{2}{6} )^{-1}+ \frac{2}{3}$

$(\frac{5}{6})^{-1} + \frac{2}{3}$

$\frac{6}{5}+ \frac{2}{3}$

$\frac{18}{15} + \frac{10}{15}$

$\frac{28}{15}$

R: b