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Вариант – 2 \( \frac{17}{33}\cdot\frac{11}{34}= \) \( \frac{75}{150}:\frac{5}{50}= \) \( \frac{8}{15}\cdot\frac{12}{120}\cdot\frac{30}{40}= \) \( \frac{7}{30}\cdot\frac{6}{21}= \) \( \frac{3}{20}:\frac{17}{10}= \) \( \frac{4}{3}\cdot\frac{12}{20}\cdot\frac{1}{5}= \) \( \frac{4}{12}\cdot\frac{18}{20}= \) \( \frac{8}{11}:\frac{4}{99}= \) \( \frac{6}{10}\cdot\frac{5}{44}\cdot\frac{2}{11}= \) \( \frac{21}{25}\cdot\frac{15}{42}= \) \( \frac{16}{17}:\frac{7}{34}= \) \( \frac{13}{50}\cdot\frac{26}{12}\cdot\frac{52}{13}= \) \( \frac{14}{24}\cdot\frac{16}{21}= \) \( \frac{12}{26}:\frac{8}{13}= \) \( \frac{3}{9}\cdot\frac{1}{6}\cdot\frac{18}{72}= \) \( \frac{50}{70}\cdot\frac{77}{150}= \) \( \frac{9}{42}:\frac{12}{21}= \) \( \frac{25}{10}\cdot\frac{65}{90}\cdot\frac{13}{45}= \) \( \frac{23}{45}\cdot\frac{9}{46}= \) \( \frac{17}{50}:\frac{18}{51}= \) \( \frac{4}{7}\cdot\frac{2}{16}\cdot\frac{2}{21}= \) \( \frac{30}{66}\cdot\frac{77}{90}= \) \( \frac{3}{10}:\frac{27}{30}= \) \( \frac{54}{8}\cdot\frac{27}{16}\cdot\frac{2}{3}= \) \( \frac{26}{32}\cdot\frac{12}{13}= \) \( \frac{4}{11}:\frac{5}{22}= \) \( \frac{11}{99}\cdot\frac{9}{88}\cdot\frac{8}{10}= \) \( \frac{8}{19}\cdot\frac{38}{40}= \) \( \frac{63}{93}:\frac{30}{31}= \) \( \frac{12}{18}\cdot\frac{24}{9}\cdot\frac{9}{48}= \)
Ответы (строки считаем сверху вниз):
| Строка | Левый столбец | Средний столбец | Правый столбец |
|---|---|---|---|
| 1 | \(\frac{1}{6}\) | \(5\) | \(\frac{1}{25}\) |
| 2 | \(\frac{1}{15}\) | \(\frac{3}{34}\) | \(\frac{4}{25}\) |
| 3 | \(\frac{3}{10}\) | \(18\) | \(\frac{3}{242}\) |
| 4 | \(\frac{3}{10}\) | \(\frac{32}{7}\) | \(\frac{169}{75}\) |
| 5 | \(\frac{4}{9}\) | \(\frac{3}{4}\) | \(\frac{1}{72}\) |
| 6 | \(\frac{11}{30}\) | \(\frac{3}{8}\) | \(\frac{169}{324}\) |
| 7 | \(\frac{1}{10}\) | \(\frac{289}{300}\) | \(\frac{1}{147}\) |
| 8 | \(\frac{7}{18}\) | \(\frac{1}{3}\) | \(\frac{243}{32}\) |
| 9 | \(\frac{3}{4}\) | \(\frac{8}{5}\) | \(\frac{1}{110}\) |
| 10 | \(\frac{2}{5}\) | \(\frac{7}{10}\) | \(\frac{1}{3}\) |
Как решать
При умножении дробей перемножаем числители и знаменатели: \[ \frac{a}{b}\cdot\frac{c}{d}=\frac{ac}{bd}. \] Но удобнее сначала сокращать общие множители.
При делении первую дробь умножаем на обратную вторую: \[ \frac{a}{b}:\frac{c}{d}=\frac{a}{b}\cdot\frac{d}{c}. \]
Например: \[ \frac{17}{33}\cdot\frac{11}{34} =\frac{17}{34}\cdot\frac{11}{33} =\frac12\cdot\frac13 =\frac16. \]
\[ \frac{3}{20}:\frac{17}{10} =\frac{3}{20}\cdot\frac{10}{17} =\frac{3}{34}. \]
В правом столбце три дроби, поэтому сокращать можно любой числитель с любым знаменателем: \[ \frac{6}{10}\cdot\frac{5}{44}\cdot\frac{2}{11} =\frac35\cdot\frac{5}{44}\cdot\frac{2}{11} =\frac{3}{44}\cdot\frac{2}{11} =\frac{3}{242}. \]
Проверка деления: \[ \frac{3}{34}\cdot\frac{17}{10}=\frac{3}{20}, \] значит \(\frac{3}{20}:\frac{17}{10}=\frac{3}{34}\) найдено верно.