Answer
-2.75
Work Step by Step
We are given the expression $-w+2x+3y+z$. We can plug in the given values to solve for the given expression.
$-w+2x+3y+z=-(4)+2(-\frac{3}{4})+3(\frac{1}{2})+1.25=-4+(\frac{2\times-3}{4})+\frac{3\times1}{2}+1.25=-4+(-\frac{6}{4})+\frac{3}{2}+1.25=-4-\frac{6}{4}+\frac{3}{2}+1.25=-4+0+1.25=1.25+(-4)=-2.75$
Recall that $-\frac{6}{4}+\frac{3}{2}=0$, as $\frac{3}{2}=\frac{3\times2}{2\times2}=\frac{6}{4}$.