[tex]9\frac{1}3*4*6\frac{1}{2}= \\ =\frac{28}3*4*\frac{13}2= \\ =\frac{28*4*13}{3*2}= \\ =\frac{28*13*2}3= \\ =\frac{728}3 \\ \\ 5\frac{3}{4}*8*2\frac{1}{2}=\frac{23}4*8*\frac{5}{2}=\frac{23*8*5}{4*2}=23*5=115[/tex]
[EDIT: Replaced x by * since x doesn't look well in typefaced math]
