Question

......,.............​

Answer 1

Пошаговое объяснение:

а)

$- 3.8 \times 1.5 = - 5.7$

б)

$- 433.62 \div ( - 5.4) = \frac{ - 43362}{ - 540} = \frac{803}{10} = 80 \frac{3}{10} = 80.3$

в)

$- 1 \frac{1}{14} \times 2 \frac{1}{3} =\left(-\frac{14+1}{14}\right)\times \left(\frac{2\times 3+1}{3}\right) =-\frac{15}{14}\times \left(\frac{2\times 3+1}{3}\right) =-\frac{15}{14}\times \left(\frac{6+1}{3}\right) =-\frac{15}{14}\times \left(\frac{7}{3}\right) =\frac{-15\times 7}{14\times 3} =\frac{-105}{42} =-\frac{5}{2} =-2.5$

г)

$1 \frac{1}{7} \div ( - 2 \frac{2}{7} ) = \frac{ \frac{7 + 1}{7} }{ - \frac{2 \times 7 + 2}{7} } = \frac{ \frac{8}{7} }{ - \frac{2 \times 7 + 2}{7} } = \frac{ \frac{8}{7} }{ - \frac{14 + 2}{7} } = \frac{ \frac{8}{7} }{ - \frac{16}{7} } = \frac{8}{7} ( - \frac{7}{16} ) = \frac{8 ( - 7)}{7 \times 16} = \frac{ - 56}{112} = - \frac{1}{2} = - 0.5$