Question:
The sum of two rational numbers is $\frac{-1}{2}$. If one of the numbers is $\frac{5}{6}$, find the other.
Solution:
Let the other number be $x$.
Now,
$x+\frac{5}{6}=\frac{-1}{2}$
$\Rightarrow x=-\frac{1}{2}-\frac{5}{6}$
$\Rightarrow x=\frac{-3-5}{6}$
$\Rightarrow x=\frac{-8}{6}$
$\Rightarrow x=\frac{-4}{3}$