Question

The sum of two rational numbers is $\frac{-3}{8}$. If one of them is $\frac{3}{16}$, find the other.

Answer 1

Step: Finding the other number
Let, two rational numbers be $p$ and $q$.

Given, $p+q=\frac{-3}{8}$
One of the numbers say $\left(p\right)=\frac{3}{16}$.
Therefore,
The other number $\left(q\right)=$ Sum of the two numbers $-$ one number
$=(p+q)-p$
$=\frac{-3}{8}-\frac{3}{16}$
$=\frac{-3\times 2}{8\times 2}-\frac{3}{16}[\text{LCM of}8\text{and}16=16]$
$=\frac{-6}{16}-\frac{3}{16}=\frac{-6-3}{16}=\frac{-9}{16}$

Hence, the other number is $\frac{-9}{16}$.