5.300 Найдите разность: a) 130 – 4; 9 б) 17-5; в) 9 - 3; г) 100 - 20.

a) $$13\frac{8}{9}-4$$

$$13\frac{8}{9}-4 = 9\frac{8}{9}$$

б) $$17\frac{5}{14} - 5\frac{3}{14}$$

$$17\frac{5}{14} - 5\frac{3}{14} = (17-5)+\frac{5-3}{14} = 12+\frac{2}{14} = 12\frac{2}{14} = 12\frac{1}{7}$$

в) $$9\frac{5}{7} - 3\frac{6}{7}$$

$$9\frac{5}{7} - 3\frac{6}{7} = 8\frac{12}{7} - 3\frac{6}{7} = (8-3) + \frac{12-6}{7} = 5 + \frac{6}{7} = 5\frac{6}{7}$$

г) $$100 - 20\frac{3}{14}$$

$$100 - 20\frac{3}{14} = 99\frac{14}{14} - 20\frac{3}{14} = (99-20) + \frac{14-3}{14} = 79 + \frac{11}{14} = 79\frac{11}{14}$$

Ответ: a) $$9\frac{8}{9}$$; б) $$12\frac{1}{7}$$; в) $$5\frac{6}{7}$$; г) $$79\frac{11}{14}$$.