Выполни действия: все выражения в вариантах А, Б и В на фото.

Правило: при умножении дробей перемножаем числители и знаменатели. При делении на дробь умножаем на обратную дробь. Результат сокращаем.

Вариант А

1. \(\frac{3}{7}\cdot\frac{1}{2}=\frac{3}{14}\)
2. \(\frac{2}{3}\cdot\frac{5}{7}=\frac{10}{21}\)
3. \(\frac{9}{10}\cdot1=\frac{9}{10}\)
4. \(2:\frac{2}{5}=2\cdot\frac{5}{2}=5\)
5. \(\frac{1}{9}:\frac{1}{3}=\frac{1}{9}\cdot3=\frac{1}{3}\)
6. \(\frac{2}{5}\cdot2=\frac{4}{5}\)
7. \(\frac{1}{2}\cdot\frac{1}{5}=\frac{1}{10}\)
8. \(\frac{4}{7}:2=\frac{4}{7}\cdot\frac{1}{2}=\frac{2}{7}\)
9. \(\frac{2}{3}\cdot\frac{1}{4}=\frac{1}{6}\)
10. \(\frac{3}{5}:1=\frac{3}{5}\)
11. \(\frac{13}{14}\cdot0=0\)
12. \(\frac{1}{7}:\frac{2}{3}=\frac{1}{7}\cdot\frac{3}{2}=\frac{3}{14}\)
13. \(1:\frac{1}{6}=6\)
14. \(\frac{5}{6}\cdot6=5\)
15. \(0:\frac{8}{9}=0\)

Ответ: \(\frac{3}{14};\ \frac{10}{21};\ \frac{9}{10};\ 5;\ \frac{1}{3};\ \frac{4}{5};\ \frac{1}{10};\ \frac{2}{7};\ \frac{1}{6};\ \frac{3}{5};\ 0;\ \frac{3}{14};\ 6;\ 5;\ 0\).

Вариант Б

1. \(\frac{1}{2}\cdot\frac{1}{7}=\frac{1}{14}\)
2. \(\frac{5}{9}\cdot1=\frac{5}{9}\)
3. \(\frac{1}{8}:\frac{1}{4}=\frac{1}{8}\cdot4=\frac{1}{2}\)
4. \(3:\frac{3}{7}=3\cdot\frac{7}{3}=7\)
5. \(\frac{4}{5}\cdot5=4\)
6. \(\frac{3}{5}\cdot\frac{5}{7}=\frac{3}{7}\)
7. \(\frac{3}{7}\cdot2=\frac{6}{7}\)
8. \(\frac{9}{10}:3=\frac{9}{10}\cdot\frac{1}{3}=\frac{3}{10}\)
9. \(0:\frac{7}{8}=0\)
10. \(\frac{1}{12}\cdot\frac{5}{9}=\frac{5}{108}\)
11. \(\frac{1}{3}\cdot\frac{1}{4}=\frac{1}{12}\)
12. \(\frac{1}{4}:\frac{3}{5}=\frac{1}{4}\cdot\frac{5}{3}=\frac{5}{12}\)
13. \(\frac{3}{5}\cdot\frac{1}{9}=\frac{1}{15}\)
14. \(\frac{15}{16}\cdot0=0\)
15. \(1:\frac{1}{3}=3\)

Ответ: \(\frac{1}{14};\ \frac{5}{9};\ \frac{1}{2};\ 7;\ 4;\ \frac{3}{7};\ \frac{6}{7};\ \frac{3}{10};\ 0;\ \frac{5}{108};\ \frac{1}{12};\ \frac{5}{12};\ \frac{1}{15};\ 0;\ 3\).

Вариант В

1. \(\frac{3}{5}\cdot\frac{5}{9}=\frac{1}{3}\)
2. \(\frac{6}{7}\cdot\frac{2}{3}=\frac{4}{7}\)
3. \(\frac{5}{6}:\frac{1}{2}=\frac{5}{3}\)
4. \(\frac{3}{7}:14=\frac{3}{98}\)
5. \(\frac{5}{12}:\frac{1}{6}=\frac{5}{2}\)
6. \(5\cdot\frac{10}{11}=\frac{50}{11}\)
7. \(\frac{2}{5}\cdot\frac{15}{16}=\frac{3}{8}\)
8. \(\frac{3}{14}:\frac{2}{7}=\frac{3}{4}\)
9. \(\frac{4}{5}\cdot\frac{5}{6}=\frac{2}{3}\)
10. \(\frac{7}{8}:14=\frac{1}{16}\)
11. \(\frac{2}{3}\cdot\frac{1}{4}=\frac{1}{6}\)
12. \(\frac{2}{15}:\frac{1}{7}=\frac{14}{15}\)
13. \(8\cdot\frac{3}{4}=6\)
14. \(\frac{1}{6}:\frac{2}{3}=\frac{1}{4}\)
15. \(\frac{4}{7}:8=\frac{1}{14}\)

Ответ: \(\frac{1}{3};\ \frac{4}{7};\ \frac{5}{3};\ \frac{3}{98};\ \frac{5}{2};\ \frac{50}{11};\ \frac{3}{8};\ \frac{3}{4};\ \frac{2}{3};\ \frac{1}{16};\ \frac{1}{6};\ \frac{14}{15};\ 6;\ \frac{1}{4};\ \frac{1}{14}\).