4.281 Найдите значение произведения: a) -2 1/3 * (-9/7); б) -3 1/7 * 4 8/11; д) 2,2 * (-1 3/7); e) -1 7/8 * (-6,75).

a) \(-2\frac{1}{3} \cdot (-\frac{9}{7}) = -\frac{7}{3} \cdot (-\frac{9}{7}) = \frac{7 \cdot 9}{3 \cdot 7} = \frac{9}{3} = 3\) б) \(-3\frac{1}{7} \cdot 4\frac{8}{11} = -\frac{22}{7} \cdot \frac{52}{11} = -\frac{2 \cdot 52}{7 \cdot 1} = -\frac{104}{7} = -14\frac{6}{7} \approx -14.86\) д) \(2.2 \cdot (-1\frac{3}{7}) = \frac{22}{10} \cdot (-\frac{10}{7}) = \frac{11}{5} \cdot (-\frac{10}{7}) = -\frac{11 \cdot 2}{1 \cdot 7} = -\frac{22}{7} = -3\frac{1}{7} \approx -3.14\) e) \(-1\frac{7}{8} \cdot (-6.75) = -\frac{15}{8} \cdot (-\frac{675}{100}) = \frac{15}{8} \cdot \frac{27}{4} = \frac{405}{32} = 12\frac{21}{32} = 12.65625\)