№2 Преобразуйте смешанное число в неправильную дробь: 1) 4\frac{1}{2}; 2) 9\frac{5}{7}; 3) 10\frac{7}{9}; 4) 7\frac{3}{18}; 5) 1\frac{12}{20}; 6) 5\frac{2}{9}; 7) 7\frac{8}{19}; 8) 4\frac{12}{13}; 9) 7\frac{3}{4}; 10) 4\frac{2}{3}.

Преобразуем смешанные числа в неправильные дроби.

1. $$4\frac{1}{2} = \frac{4 \cdot 2 + 1}{2} = \frac{8 + 1}{2} = \frac{9}{2}$$
2. $$9\frac{5}{7} = \frac{9 \cdot 7 + 5}{7} = \frac{63 + 5}{7} = \frac{68}{7}$$
3. $$10\frac{7}{9} = \frac{10 \cdot 9 + 7}{9} = \frac{90 + 7}{9} = \frac{97}{9}$$
4. $$7\frac{3}{18} = \frac{7 \cdot 18 + 3}{18} = \frac{126 + 3}{18} = \frac{129}{18}$$
5. $$1\frac{12}{20} = \frac{1 \cdot 20 + 12}{20} = \frac{20 + 12}{20} = \frac{32}{20}$$
6. $$5\frac{2}{9} = \frac{5 \cdot 9 + 2}{9} = \frac{45 + 2}{9} = \frac{47}{9}$$
7. $$7\frac{8}{19} = \frac{7 \cdot 19 + 8}{19} = \frac{133 + 8}{19} = \frac{141}{19}$$
8. $$4\frac{12}{13} = \frac{4 \cdot 13 + 12}{13} = \frac{52 + 12}{13} = \frac{64}{13}$$
9. $$7\frac{3}{4} = \frac{7 \cdot 4 + 3}{4} = \frac{28 + 3}{4} = \frac{31}{4}$$
10. $$4\frac{2}{3} = \frac{4 \cdot 3 + 2}{3} = \frac{12 + 2}{3} = \frac{14}{3}$$

Ответ: $$4\frac{1}{2} = \frac{9}{2}; 9\frac{5}{7} = \frac{68}{7}; 10\frac{7}{9} = \frac{97}{9}; 7\frac{3}{18} = \frac{129}{18}; 1\frac{12}{20} = \frac{32}{20}; 5\frac{2}{9} = \frac{47}{9}; 7\frac{8}{19} = \frac{141}{19}; 4\frac{12}{13} = \frac{64}{13}; 7\frac{3}{4} = \frac{31}{4}; 4\frac{2}{3} = \frac{14}{3}$$