Question

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

Answer 1

Given, sum of the numbers $=\frac{-3}{5}$
One of the numbers $=\frac{-9}{10}$
Then the other number
$=$ Sum of the numbers $-$ One of the numbers
$=\frac{-3}{5}-\frac{-9}{10}=\frac{-3}{5}+\frac{9}{10}$
$=\frac{-3\times 2+9\times 1}{10}=\frac{-6+9}{10}=\frac{3}{10}$
Therefore the required number is $\frac{3}{10}$