Question

The sum of two rational numbers is $\frac{-3}{5}$. If one of them is $\frac{-9}{10}$, find the other number.

Answer 1

Given that sum of the numbers $=\frac{-3}{5}$
one of the number $=\frac{-9}{10}$
The other number = sum of the numbers - given number
$=\frac{-3}{5}-\left(\frac{-9}{10}\right)$
$=\frac{-3}{5}+\frac{9}{10}$
$=\frac{-6}{10}+\frac{9}{10}$
$=\frac{-6+9}{10}=\frac{3}{10}$
Therefore other number is $\frac{3}{10}$