Задание № 2 a) \frac{12}{17}×(\frac{11}{24}-\frac{3}{8}) б) \frac{9}{35}×(\frac{7}{24}+\frac{1}{18}) в) \frac{25}{27}-\frac{10}{21}÷\frac{15}{28} г) 2\frac{2}{9}÷\frac{4}{3}+\frac{1}{3} д) 18×\frac{5}{84}-\frac{17}{21} e) (\frac{4}{7}+\frac{2}{3})÷\frac{13}{3} ж) 1-\frac{3}{4}×2\frac{2}{5} з) 1\frac{1}{8}+\frac{3}{7}-\frac{47}{56}

• а)
  Показать решение

  \[\frac{12}{17} \times (\frac{11}{24} - \frac{3}{8}) = \frac{12}{17} \times (\frac{11}{24} - \frac{9}{24}) = \frac{12}{17} \times \frac{2}{24} = \frac{12}{17} \times \frac{1}{12} = \frac{1}{17}\]
• б)
  Показать решение

  \[\frac{9}{35} \times (\frac{7}{24} + \frac{1}{18}) = \frac{9}{35} \times (\frac{21}{72} + \frac{4}{72}) = \frac{9}{35} \times \frac{25}{72} = \frac{1}{7} \times \frac{5}{8} = \frac{5}{56}\]
• в)
  Показать решение

  \[\frac{25}{27} - \frac{10}{21} \div \frac{15}{28} = \frac{25}{27} - \frac{10}{21} \times \frac{28}{15} = \frac{25}{27} - \frac{2}{3} \times \frac{4}{3} = \frac{25}{27} - \frac{8}{9} = \frac{25}{27} - \frac{24}{27} = \frac{1}{27}\]
• г)
  Показать решение

  \[2\frac{2}{9} \div \frac{4}{3} + \frac{1}{3} = \frac{20}{9} \div \frac{4}{3} + \frac{1}{3} = \frac{20}{9} \times \frac{3}{4} + \frac{1}{3} = \frac{5}{3} + \frac{1}{3} = \frac{6}{3} = 2\]
• д)
  Показать решение

  \[18 \times \frac{5}{84} - \frac{17}{21} = 18 \times \frac{5}{84} - \frac{17}{21} = \frac{3}{1} \times \frac{5}{14} - \frac{17}{21} = \frac{15}{14} - \frac{17}{21} = \frac{45}{42} - \frac{34}{42} = \frac{11}{42}\]
• е)
  Показать решение

  \[(\frac{4}{7} + \frac{2}{3}) \div \frac{13}{3} = (\frac{12}{21} + \frac{14}{21}) \div \frac{13}{3} = \frac{26}{21} \div \frac{13}{3} = \frac{26}{21} \times \frac{3}{13} = \frac{2}{7} \times \frac{1}{1} = \frac{2}{7}\]
• ж)
  Показать решение

  \[1 - \frac{3}{4} \times 2\frac{2}{5} = 1 - \frac{3}{4} \times \frac{12}{5} = 1 - \frac{3}{1} \times \frac{3}{5} = 1 - \frac{9}{5} = \frac{5}{5} - \frac{9}{5} = -\frac{4}{5}\]
• з)
  Показать решение

  \[1\frac{1}{8} + \frac{3}{7} - \frac{47}{56} = \frac{9}{8} + \frac{3}{7} - \frac{47}{56} = \frac{63}{56} + \frac{24}{56} - \frac{47}{56} = \frac{87}{56} - \frac{47}{56} = \frac{40}{56} = \frac{5}{7}\]

Ответ:

• а) \(\frac{1}{17}\)
• б) \(\frac{5}{56}\)
• в) \(\frac{1}{27}\)
• г) 2
• д) \(\frac{11}{42}\)
• е) \(\frac{2}{7}\)
• ж) \(-\frac{4}{5}\)
• з) \(\frac{5}{7}\)