8. а) $$ \frac{1,7}{0,51} - \frac{2,4}{0,36} = \frac{170}{51} - \frac{240}{36} = \frac{10}{3} - \frac{20}{3} = -\frac{10}{3} $$
б) $$ \frac{0,08}{0,02} - \frac{6}{22} = \frac{8}{2} - \frac{3}{11} = 4 - \frac{3}{11} = \frac{44}{11} - \frac{3}{11} = \frac{41}{11} $$
9. a) $$ \frac{0,5 - 0,6}{0,3 - 1,5} = \frac{-0,1}{-1,2} = \frac{0,1}{1,2} = \frac{1}{12} $$
б) $$ \frac{1,1 - 0,4}{0,05 - 0,23} = \frac{0,7}{-0,18} = -\frac{0,7}{0,18} = -\frac{70}{18} = -\frac{35}{9} $$
в) $$ \frac{1,5 - 0,8}{1,3 - 0,6} = \frac{0,7}{0,7} = 1 $$
г) $$ \frac{0,07}{0,4 - 3,5} = \frac{0,07}{-3,1} = -\frac{7}{310} $$
в) $$ \frac{0,7 - 0,26}{1,3 - 0,6} = \frac{0,44}{0,7} = \frac{44}{70} = \frac{22}{35} $$
г) $$ \frac{0,05 - 0,23}{4,6 - 0,02} = \frac{-0,18}{4,58} = -\frac{18}{458} = -\frac{9}{229} $$
Ответ: 8. а) -10/3; б) 41/11; 9. a) 1/12; б) -35/9; в) 1; г) -7/310; в) 22/35; г) -9/229.