Answer:[tex](m+p,n+r)[/tex]Step-by-step explanation:Let [tex](x_1,y_1)=A(2m,2n)[/tex] and [tex](x_2,y_2)=C(2p,2r)[/tex].The midpoint is calculated using the formula;[tex]M=(\frac{x_1+x_2}{2},\frac{y_1+y_2}{2})[/tex]Substitute the coordinates to get;[tex]M=(\frac{2m+2p}{2},\frac{2n+2r}{2})[/tex][tex]M=(\frac{2(m+p)}{2},\frac{2(n+r)}{2})[/tex][tex]M=(m+p,n+r)[/tex]