Answer
Q=5
Work Step by Step
Let M be the midpoint of P and R. Use the midpoint formula to find M.
$M=\frac{P+R}{2}=\frac{-4+8}{2}=\frac{4}{2}=2$
The point $\frac{3}{4}$ from P to R is the midpoint of M and R. Use the midpoint formula to find Q.
$Q=\frac{M+R}{2}=\frac{2+8}{2}=\frac{10}{2}=5$