Решим примеры.
6) $$1\frac{2}{3} + 2\frac{1}{4} = 1\frac{8}{12} + 2\frac{3}{12} = 3\frac{11}{12}$$
Ответ: 3$$\frac{11}{12}$$
7) $$3\frac{3}{4} + 2\frac{1}{6} = 3\frac{9}{12} + 2\frac{2}{12} = 5\frac{11}{12}$$
Ответ: 5$$\frac{11}{12}$$
8) $$1\frac{4}{5} + \frac{2}{3} = 1\frac{12}{15} + \frac{10}{15} = 1\frac{22}{15} = 2\frac{7}{15}$$
Ответ: 2$$\frac{7}{15}$$
9) $$4\frac{6}{7} - 1\frac{11}{15} = 4\frac{90}{105} - 1\frac{77}{105} = 3\frac{13}{105}$$
Ответ: 3$$\frac{13}{105}$$
10) $$5\frac{1}{4} - 1\frac{4}{5} = 5\frac{5}{20} - 1\frac{16}{20} = 4\frac{25}{20} - 1\frac{16}{20} = 3\frac{9}{20}$$
Ответ: 3$$\frac{9}{20}$$
6) $$1\frac{8}{9} + 2\frac{5}{8} = 1\frac{64}{72} + 2\frac{45}{72} = 3\frac{109}{72} = 4\frac{37}{72}$$
Ответ: 4$$\frac{37}{72}$$
7) $$2\frac{4}{5} + \frac{2}{3} = 2\frac{12}{15} + \frac{10}{15} = 2\frac{22}{15} = 3\frac{7}{15}$$
Ответ: 3$$\frac{7}{15}$$
8) $$3\frac{7}{9} - 1\frac{5}{8} = 3\frac{56}{72} - 1\frac{45}{72} = 2\frac{11}{72}$$
Ответ: 2$$\frac{11}{72}$$
9) $$2\frac{14}{15} - 1\frac{7}{10} = 2\frac{28}{30} - 1\frac{21}{30} = 1\frac{7}{30}$$
Ответ: 1$$\frac{7}{30}$$
10) $$8\frac{6}{7} - 5\frac{13}{14} = 8\frac{12}{14} - 5\frac{13}{14} = 7\frac{26}{14} - 5\frac{13}{14} = 2\frac{13}{14}$$
Ответ: 2$$\frac{13}{14}$$