Question

By what number should ${\left(\frac{1}{2}\right)}^{-1}$ be multiplied so that the product many be equal to ${\left(\frac{-4}{7}\right)}^{-1}?$

Answer 1

$Letxbetherequirednumber,thenx\times {\left(\frac{1}{2}\right)}^{-1}={\left(\frac{-4}{7}\right)}^{-1}\Rightarrow x(2{)}^1={\left(\frac{-7}{4}\right)}^1\Rightarrow 2x=\frac{-7}{4}\Rightarrow x=\frac{-7}{4\times 2}=\frac{-7}{8}\therefore Requirednumber=\frac{-7}{8}$