а) 2 \frac{4}{9} - 3 \frac{5}{6} = б) -\frac{6}{7} - \frac{5}{21} = в) -4 \frac{1}{7} \cdot (-\frac{12}{29}) = г) 1 \frac{2}{13} : (-\frac{7}{39}) =

Решение:

а) 2 \frac{4}{9} - 3 \frac{5}{6} = \frac{22}{9} - \frac{23}{6} = \frac{44}{18} - \frac{69}{18} = - \frac{25}{18} = -1 \frac{7}{18} б) -\frac{6}{7} - \frac{5}{21} = -\frac{18}{21} - \frac{5}{21} = - \frac{23}{21} = -1 \frac{2}{21} в) -4 \frac{1}{7} \cdot (-\frac{12}{29}) = -\frac{29}{7} \cdot (-\frac{12}{29}) = \frac{1}{7} \cdot 12 = \frac{12}{7} = 1 \frac{5}{7} г) 1 \frac{2}{13} : (-\frac{7}{39}) = \frac{15}{13} : (-\frac{7}{39}) = \frac{15}{13} \cdot (-\frac{39}{7}) = \frac{15}{1} \cdot (-\frac{3}{7}) = -\frac{45}{7} = -6 \frac{3}{7}

Ответ:

• a) -1 \frac{7}{18}
• б) -1 \frac{2}{21}
• в) 1 \frac{5}{7}
• г) -6 \frac{3}{7}