Вычислите: 2 22/31 * 1/2; 1 33/43 * 4 10/19 * 3 5/8; 21/32 * 5/6 * 8/15 * 1/2; 8 2/3 * 5/6 * 1 1/35 * 1 3/4. Выполните деление: 9 : 6/19; 20/27 : 2; 4/9 : 2/15; 5 1/2 : 2 1/4.

7. $2\frac{22}{31} \cdot \frac{1}{2} = \frac{84}{31} \cdot \frac{1}{2} = \frac{42}{31} = 1\frac{11}{31}$ 8. $1\frac{33}{43} \cdot 4\frac{10}{19} \cdot 3\frac{5}{8} = \frac{76}{43} \cdot \frac{86}{19} \cdot \frac{29}{8} = \frac{76 \cdot 2 \cdot 29}{19 \cdot 8} = \frac{4 \cdot 2 \cdot 29}{8} = 29$ 9. $\frac{21}{32} \cdot \frac{5}{6} \cdot \frac{8}{15} \cdot \frac{1}{2} = \frac{21 \cdot 5 \cdot 8 \cdot 1}{32 \cdot 6 \cdot 15 \cdot 2} = \frac{7 \cdot 1 \cdot 1 \cdot 1}{4 \cdot 2 \cdot 3 \cdot 2} = \frac{7}{48}$ 10. $8\frac{2}{3} \cdot \frac{5}{6} \cdot 1\frac{1}{35} \cdot 1\frac{3}{4} = \frac{26}{3} \cdot \frac{5}{6} \cdot \frac{36}{35} \cdot \frac{7}{4} = \frac{26 \cdot 5 \cdot 36 \cdot 7}{3 \cdot 6 \cdot 35 \cdot 4} = \frac{13 \cdot 1 \cdot 6 \cdot 1}{3 \cdot 1 \cdot 1 \cdot 2} = \frac{13 \cdot 3}{3} = 13$ 11. $9 : \frac{6}{19} = 9 \cdot \frac{19}{6} = \frac{3 \cdot 19}{2} = \frac{57}{2} = 28\frac{1}{2}$ 12. $\frac{20}{27} : 2 = \frac{20}{27 \cdot 2} = \frac{10}{27}$ 13. $\frac{4}{9} : \frac{2}{15} = \frac{4}{9} \cdot \frac{15}{2} = \frac{2 \cdot 5}{3} = \frac{10}{3} = 3\frac{1}{3}$ 14. $5\frac{1}{2} : 2\frac{1}{4} = \frac{11}{2} : \frac{9}{4} = \frac{11}{2} \cdot \frac{4}{9} = \frac{11 \cdot 2}{9} = \frac{22}{9} = 2\frac{4}{9}$