[tex]$\frac{7}{8} \cdot \frac{2}{5} =\frac{7\cdot \:2}{8\cdot \:5} =\frac{7\cdot \:2}{2\cdot \:4\cdot \:5} =\frac{7}{4\cdot \:5} =\frac{7}{20}[/tex]
[tex]$\frac{36}{44}\cdot \frac{11}{12} =\frac{9}{11}\cdot \frac{11}{12} =\frac{9}{12} =\frac{3}{4}[/tex]
[tex]$3\frac{12}{16}\cdot \frac{4}{10} =\frac{60}{16}\cdot \frac{4}{10}=\frac{15}{4}\cdot \frac{4}{10}=\frac{15}{10} = \frac{3}{2}[/tex]
[tex]$2\frac{1}{4}\cdot \:1\frac{23}{45} =\frac{9}{4}\cdot \:1\frac{23}{45} =\frac{9\cdot \:68}{4\cdot \:45} =\frac{9\cdot \:68}{4\cdot \:9\cdot \:5} =\frac{68}{4\cdot \:5} =\frac{4\cdot \:17}{4\cdot \:5} =\frac{17}{5}[/tex]
