Question

By what number should $(-6{)}^{-1}$ be multiplied so that the product becomes $9^{-1}$ ?

Answer 1

Let x be the required number which is multiplied

$\therefore (-6{)}^{-1}\times x=9^{-1}\Rightarrow \left(\frac{1}{-6}\right)\times x=\frac{1}{9}$

$x=\frac{1}{9}\times \frac{-6}{1}=\frac{-2}{3}$

Hence, required number $=\frac{-2}{3}$