Question

Which expression simplifies 2/5 ? A) (-1/10)-(-1/2) B) (-1/10)+(-1/2) C) (-1/10)×(-1/2) D) (-1/10)÷(-1/2)

Answer 1

$\bf -\cfrac{1}{10}-\left( -\cfrac{1}{2} \right)\implies -\cfrac{1}{10}+\cfrac{1}{2}\implies \stackrel{\textit{using the LCD of 10}}{\cfrac{-(1)1~~+~~(5)1}{10}}\implies \cfrac{-1+5}{10} \\\\\\ \cfrac{4}{10}\implies \stackrel{simplified}{\cfrac{2}{5}}$