1) $$1\frac{1}{6}:2\frac{1}{4}=$$ 2) $$5\frac{1}{11}-3=$$ 3) $$2\frac{1}{12}+4\frac{7}{10}=$$ 4) $$3\frac{1}{2}-2\frac{4}{7}=$$ 5) $$4\frac{11}{18}+\frac{7}{9}=$$ 6) $$3\frac{6}{7}:\frac{1}{3}=$$ 7) $$5\frac{5}{6}-2\frac{5}{14}=$$ 8) $$4-\frac{1}{19}=$$ 9) $$3\frac{9}{17}:1\frac{13}{17}=$$ 10) $$\frac{2}{3}:2\frac{1}{4}=$$ 11) $$2\frac{9}{10}+3\frac{5}{6}=$$ 12) $$2\frac{1}{2}\cdot2=$$

Решим примеры по порядку.

1. $$1\frac{1}{6}:2\frac{1}{4}= \frac{7}{6}:\frac{9}{4}=\frac{7}{6}\cdot\frac{4}{9}=\frac{7\cdot2}{3\cdot9}=\frac{14}{27}$$
2. $$5\frac{1}{11}-3=2\frac{1}{11}$$
3. $$2\frac{1}{12}+4\frac{7}{10}=2\frac{5}{60}+4\frac{42}{60}=6\frac{47}{60}$$
4. $$3\frac{1}{2}-2\frac{4}{7}=3\frac{7}{14}-2\frac{8}{14}=2\frac{21}{14}-2\frac{8}{14}=\frac{13}{14}$$
5. $$4\frac{11}{18}+\frac{7}{9}=4\frac{11}{18}+\frac{14}{18}=4\frac{25}{18}=5\frac{7}{18}$$
6. $$3\frac{6}{7}:\frac{1}{3}=\frac{27}{7}:\frac{1}{3}=\frac{27}{7}\cdot3=\frac{81}{7}=11\frac{4}{7}$$
7. $$5\frac{5}{6}-2\frac{5}{14}=5\frac{35}{42}-2\frac{15}{42}=3\frac{20}{42}=3\frac{10}{21}$$
8. $$4-\frac{1}{19}=3\frac{19}{19}-\frac{1}{19}=3\frac{18}{19}$$
9. $$3\frac{9}{17}:1\frac{13}{17}=\frac{60}{17}:\frac{30}{17}=\frac{60}{17}\cdot\frac{17}{30}=2$$
10. $$\frac{2}{3}:2\frac{1}{4}=\frac{2}{3}:\frac{9}{4}=\frac{2}{3}\cdot\frac{4}{9}=\frac{8}{27}$$
11. $$2\frac{9}{10}+3\frac{5}{6}=2\frac{27}{30}+3\frac{25}{30}=5\frac{52}{30}=6\frac{22}{30}=6\frac{11}{15}$$
12. $$2\frac{1}{2}\cdot2=\frac{5}{2}\cdot2=5$$

Ответ: 1) $$\frac{14}{27}$$; 2) $$2\frac{1}{11}$$; 3) $$6\frac{47}{60}$$; 4) $$\frac{13}{14}$$; 5) $$5\frac{7}{18}$$; 6) $$11\frac{4}{7}$$; 7) $$3\frac{10}{21}$$; 8) $$3\frac{18}{19}$$; 9) $$2$$; 10) $$\frac{8}{27}$$; 11) $$6\frac{11}{15}$$; 12) $$5$$