4. [tex]\frac{16}{25}\cdot \frac{5}{24} = \frac{16}{5}\cdot \frac{1}{24} = \frac{2}{5}\cdot \frac{1}{3}=\frac{2}{5\cdot \:3}=\frac{2}{15}[/tex]
5. [tex]\frac{8}{21}\cdot \:8\frac{3}{4} = \frac{8}{21}\cdot \frac{35}{4} = \frac{2}{21}\cdot 35 = \frac{2}{3}\cdot 5 = \frac{10}{3} = 3\frac{1}{3}[/tex]
6. [tex]3\frac{4}{15}\cdot \:1\frac{3}{7} = \frac{49}{15}\cdot \frac{10}{7} = \frac{7}{15}\cdot 10 = \frac{7}{3}\cdot2 = \frac{14}{3} = 4\frac{2}{3}[/tex]
7. [tex]\frac{32}{25}\cdot \frac{15}{16}\cdot \frac{5}{9}=\frac{2}{25}\cdot 15\cdot \frac{5}{9}=\frac{2}{5}\cdot \frac{1}{9}\cdot 15=2\cdot 3\cdot \frac{1}{9} =\frac{2}{3}[/tex]
8. [tex]\frac{5}{4}\cdot \:1\frac{13}{15}\cdot \frac{8}{7} =\frac{5}{4}\cdot \frac{28}{15}\cdot \frac{8}{7}=5\cdot \frac{7}{15}\cdot \frac{8}{7} =5\cdot \frac{8}{15}=\frac{8}{3}=2\frac{2}{3}[/tex]
