Answer
a) $\frac{1}{4}$ or $0.25$
b) 1
Work Step by Step
a) By first considering the expression without absolute value signs, you see that $\frac{-6}{24}$ simplifies to $\frac{-1}{4}$. Then you can add back the absolute value signs, and because this is less than zero, you multiply by $-1$ to get $\frac{1}{4}$.
b) First, evaluate the top and bottom expressions of the fraction. $7-12$ is $-5$, and $12-7$ is $5$. This leaves the fraction at $\frac{-5}{5}$, which simplifies to $\frac{-1}{1}$ which is simply $-1$. Considering the absolute value signs again, this is less than zero, so we multiply by negative one. $(-1)(-1)$ is $1$.