\[\left( 18 - 10\frac{5}{9} \right) - \left( 6\frac{1^{\backslash 3}}{8} - 3\frac{2^{\backslash 8}}{3} \right) =\]
\[= \left( 17\frac{9}{9} - 10\frac{5}{9} \right) - \left( 6\frac{3}{24} - 3\frac{16}{24} \right) =\]
\[= 7\frac{4}{9} - \left( 5\frac{27}{24} - 3\frac{16}{24} \right) =\]
\[= 7\frac{4^{\backslash 8}}{9} - 2\frac{11^{\backslash 3}}{24} = 7\frac{32}{72} - 2\frac{33}{72} =\]
\[= 6\frac{104}{72} - 2\frac{33}{72} = 4\frac{71}{72}\]