Давай разберем по порядку каждый пример:
a) $$1\frac{11}{15}-1 = \frac{11}{15}$$
б) $$1\frac{11}{15}-\frac{4}{15} = 1\frac{11-4}{15} = 1\frac{7}{15}$$
в) $$1\frac{11}{15}-\frac{11}{15} = 1\frac{11}{15}-\frac{11}{15} = 1$$
г) $$1\frac{11}{15}-\frac{13}{15} = \frac{26}{15} - \frac{13}{15} = \frac{26-13}{15} = \frac{13}{15}$$
a) $$2\frac{5}{8}-\frac{3}{8} = 2\frac{5-3}{8} = 2\frac{2}{8} = 2\frac{1}{4}$$
б) $$2\frac{5}{8}-1\frac{3}{8} = (2-1) + \frac{5-3}{8} = 1 + \frac{2}{8} = 1\frac{1}{4}$$
в) $$2\frac{5}{8}-\frac{7}{8} = \frac{21}{8} - \frac{7}{8} = \frac{21-7}{8} = \frac{14}{8} = \frac{7}{4} = 1\frac{3}{4}$$
г) $$2\frac{5}{8}-1\frac{7}{8} = \frac{21}{8} - \frac{15}{8} = \frac{21-15}{8} = \frac{6}{8} = \frac{3}{4}$$
a) $$3\frac{9}{17}-\frac{5}{17} = 3\frac{9-5}{17} = 3\frac{4}{17}$$
б) $$3\frac{9}{17}-1\frac{5}{17} = (3-1) + \frac{9-5}{17} = 2 + \frac{4}{17} = 2\frac{4}{17}$$
в) $$3\frac{9}{17}-\frac{10}{17} = \frac{60}{17} - \frac{10}{17} = \frac{60-10}{17} = \frac{50}{17} = 2\frac{16}{17}$$
г) $$3\frac{9}{17}-1\frac{10}{17} = (3-1) + \frac{9-10}{17} = 2 - \frac{1}{17} = \frac{34}{17} - \frac{1}{17} = \frac{33}{17} = 1\frac{16}{17}$$
Ответ: См. решение
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