2. Сравнить дроби: a) 7 12 и 3 4 ; б) 2 3 и 5 8 ; в) 8 21 и 5 14 ; г) 9 20 и 7 16 ; д) 7 15 и 11 6 ; ж) 15 11 и 11 13

2. Сравнить дроби:

a) $$\frac{7}{12}$$ и $$\frac{3}{4} = \frac{3 \cdot 3}{4 \cdot 3} = \frac{9}{12}$$

$$\frac{7}{12} < \frac{9}{12}$$

Ответ: 7/12 < 3/4

б) $$\frac{2}{3} = \frac{2 \cdot 8}{3 \cdot 8} = \frac{16}{24}$$ и $$\frac{5}{8} = \frac{5 \cdot 3}{8 \cdot 3} = \frac{15}{24}$$

$$\frac{16}{24} > \frac{15}{24}$$

Ответ: 2/3 > 5/8

в) $$\frac{8}{21} = \frac{8 \cdot 2}{21 \cdot 2} = \frac{16}{42}$$ и $$\frac{5}{14} = \frac{5 \cdot 3}{14 \cdot 3} = \frac{15}{42}$$

$$\frac{16}{42} > \frac{15}{42}$$

Ответ: 8/21 > 5/14

г) $$\frac{9}{20} = \frac{9 \cdot 4}{20 \cdot 4} = \frac{36}{80}$$ и $$\frac{7}{16} = \frac{7 \cdot 5}{16 \cdot 5} = \frac{35}{80}$$

$$\frac{36}{80} > \frac{35}{80}$$

Ответ: 9/20 > 7/16

д) $$\frac{7}{15} = \frac{7 \cdot 2}{15 \cdot 2} = \frac{14}{30}$$ и $$\frac{11}{6} = \frac{11 \cdot 5}{6 \cdot 5} = \frac{55}{30}$$

$$\frac{14}{30} < \frac{55}{30}$$

Ответ: 7/15 < 11/6

ж) $$\frac{15}{11}$$ и $$\frac{11}{13}$$

$$\frac{15}{11} > 1$$ и $$\frac{11}{13} < 1$$

Ответ: 15/11 > 11/13