Question

What is the multiplicative inverse of $-1\frac{1}{7}$?

Answer 1

We know that the product of a number with its multiplicative inverse is 1.
Given number is $-1\frac{1}{7}$ , i.e. $\frac{-8}{7}$.
Let it's multiplicative inverse be $x$.
$\Rightarrow \frac{-8}{7}\times x=1$
$\Rightarrow x=1\times \left(\frac{-7}{8}\right)$ [by cross-multiplication]
$=\frac{-7}{8}$
Hence, $\frac{-7}{8}$ is the multiplicative inverse of $-1\frac{1}{7}$.