4.283 Выполните действия: г) (-\frac{1}{3} - \frac{4}{7} - \frac{20}{21}) \cdot \frac{7}{13} + \frac{11}{25}; д) (6 - 4,2) (-\frac{9}{16}) - 4,23; e) (-\frac{1}{4} - 0,75 - \frac{1}{5}) \cdot (-\frac{2}{3}) + 4,2.

Ответ:

г)

\[\left(-\frac{1}{3} - \frac{4}{7} - \frac{20}{21}\right) \cdot \frac{7}{13} + \frac{11}{25} = \left(-\frac{7}{21} - \frac{12}{21} - \frac{20}{21}\right) \cdot \frac{7}{13} + \frac{11}{25} = \]

\[= \left(-\frac{39}{21}\right) \cdot \frac{7}{13} + \frac{11}{25} = -\frac{3}{3} \cdot \frac{1}{1} + \frac{11}{25} = -1 + \frac{11}{25} = -\frac{25}{25} + \frac{11}{25} = -\frac{14}{25}\]

д)

\[\left(6\frac{1}{3} - 4,2\right) \cdot \left(-\frac{9}{16}\right) - 4,23 = \left(\frac{19}{3} - 4,2\right) \cdot \left(-\frac{9}{16}\right) - 4,23 = \left(\frac{19}{3} - \frac{42}{10}\right) \cdot \left(-\frac{9}{16}\right) - 4,23 = \]

\[= \left(\frac{190}{30} - \frac{126}{30}\right) \cdot \left(-\frac{9}{16}\right) - 4,23 = \frac{64}{30} \cdot \left(-\frac{9}{16}\right) - 4,23 = \frac{4}{10} \cdot (-3) - 4,23 = -1,2 - 4,23 = -5,43\]

е)

\[\left(-\frac{1}{4} - 0,75 - \frac{1}{5}\right) \cdot \left(-\frac{2}{3}\right) + 4,2 = \left(-\frac{1}{4} - \frac{3}{4} - \frac{1}{5}\right) \cdot \left(-\frac{2}{3}\right) + 4,2 = \left(-\frac{4}{4} - \frac{1}{5}\right) \cdot \left(-\frac{2}{3}\right) + 4,2 = \]

\[= \left(-1 - \frac{1}{5}\right) \cdot \left(-\frac{2}{3}\right) + 4,2 = \left(-\frac{6}{5}\right) \cdot \left(-\frac{2}{3}\right) + 4,2 = \frac{12}{15} + 4,2 = \frac{4}{5} + 4,2 = 0,8 + 4,2 = 5\]

Ответ:

г) \[-\frac{14}{25}\]

д) \[-5,43\]

е) \[5\]