Выполните действия:
1) −2,7 * (−1,2) + 3,5 * (−2,8);
2) −7,4 * 0,6 − 3,8 * (−2,3);
3) (−9,3 − 1,7) * (2,6 + (−5,9));
4) $4\frac{7}{12} * (-1\frac{3}{11}) - (-1\frac{1}{15}) * (-\frac{45}{64})$;
5) $-\frac{81}{88} * (-6 + (-1\frac{13}{15}) * (-1\frac{19}{21}))$;
6) $(-\frac{4}{5} - \frac{4}{7}) * (5\frac{7}{9} - 7\frac{11}{12})$.
−2,7 * (−1,2) + 3,5 * (−2,8) = 3,24 − 9,8 = −6,56
−7,4 * 0,6 − 3,8 * (−2,3) = −4,44 + 8,74 = 4,3
(−9,3 − 1,7) * (2,6 + (−5,9)) = −11 * 3,3 = −36,3
$4\frac{7}{12} * (-1\frac{3}{11}) - (-1\frac{1}{15}) * (-\frac{45}{64}) = \frac{55}{12} * (-\frac{14}{11}) - (-\frac{16}{15}) * (-\frac{45}{64}) = \frac{5}{6} * (-\frac{7}{1}) - (-\frac{1}{1}) * (-\frac{3}{4}) = -\frac{35}{6} - \frac{3}{4} = -5\frac{5}{6} - \frac{3}{4} = -5\frac{10}{12} - \frac{9}{12} = -5\frac{19}{12} = -6\frac{7}{12}$
$-\frac{81}{88} * (-6 + (-1\frac{13}{15}) * (-1\frac{19}{21})) = -\frac{81}{88} * (-6 + (-\frac{28}{15}) * (-\frac{40}{21})) = -\frac{81}{88} * (-6 + (-\frac{4}{3}) * (-\frac{8}{3})) = -\frac{81}{88} * (-6 + \frac{32}{9}) = -\frac{81}{88} * (-6 + 3\frac{5}{9}) = -\frac{81}{88} * -2\frac{4}{9} = -\frac{81}{88} * -\frac{22}{9} = -\frac{9}{4} * -\frac{1}{1} = \frac{9}{4} = 2\frac{1}{4}$
$(-\frac{4}{5} - \frac{4}{7}) * (5\frac{7}{9} - 7\frac{11}{12}) = (-\frac{28}{35} - \frac{20}{35}) * (5\frac{28}{36} - 7\frac{33}{36}) = -\frac{48}{35} * -2\frac{5}{36} = -\frac{48}{35} * -\frac{77}{36} = -\frac{4}{5} * -\frac{11}{3} = \frac{44}{15} = 2\frac{14}{15}$
Пожауйста, оцените решение