$4\frac{1}{2}:\frac{1}{2}=\frac{9}{2}\cdot \frac{2}{1}=\frac{18}{2}=9$

$1\frac{3}{4}:\frac{5}{6}=\frac{7}{4}\cdot \frac{6}{5}=\frac{42}{20}=2\frac{1}{10}$

$2:\frac{1}{4}=2\cdot \frac{4}{1}=\frac{8}{1}=8$

$4\frac{2}{3}:\frac{5}{12}=\frac{14}{3}\cdot \frac{12}{5}=\frac{168}{15}=11\frac{1}{5}$

$\frac{1}{2}:\frac{1}{4}=\frac{1}{2}\cdot \frac{4}{1}=\frac{4}{2}=2$

$\frac{5}{6}:\frac{5}{12}=\frac{5}{6}\cdot \frac{12}{5}=\frac{60}{30}=2$

$\frac{1}{2}:2=\frac{1}{2}\cdot \frac{1}{2}=\frac{1}{4}$

$11\frac{1}{4}:6=\frac{45}{4}\cdot \frac{1}{6}=\frac{45}{24}=1\frac{7}{8}$

$16\cdot \frac{3}{2}=\frac{48}{2}=24$

$28\cdot \frac{3}{1}=\frac{84}{1}=84$

$16\cdot \frac{7}{4}=\frac{112}{4}=28$

$28\cdot \frac{3}{4}=\frac{84}{4}=21$

$\frac{2}{3}\cdot \frac{7}{4}=\frac{14}{12}=1\frac{1}{6}$

$28\cdot \frac{3}{8}=\frac{84}{8}=10\frac{1}{2}$

$\frac{4}{7}\cdot \frac{3}{2}=\frac{12}{14}=\frac{6}{7}$

$28\cdot \frac{10}{3}=\frac{280}{3}=93\frac{1}{3}$