[tex]2\frac{1}{7} : 10 = \frac{15}{7} : 10 = \frac{\not15^{3} }{7} * \frac{1}{\not10^{2} } = \frac{3}{14}[/tex]
[tex]6\frac{2}{3} : 4 = \frac{20}{3} : 4 = \frac{\not20^{5} }{3} * \frac{1}{\not4^{1} } = \frac{5}{3} = 1\frac{2}{3}[/tex]
[tex]6\frac{3}{5} : 12 = \frac{33}{5 } : 12 = \frac{\not33^{11} }{5 } * \frac{1}{\not12^{4} } =\frac{11}{20}[/tex]