Question

Даю 55 баллов
1) 2 3/9:(1 - 2/7)
2) 1 5/6 : (2/3 - 3/7)
3)2 1/3 : (5/8 - 8/3) - 2 × 1 3/7
4) -190 + 39 - 34 + 235 49 : (84 - 91)​

Answer 1

1)

$2 \frac{3}{9} \div (1 - \frac{2}{7} ) = \frac{21}{9} \div \frac{5}{7} = \frac{7}{3} \times \frac{7}{5} = \frac{49}{15} = 3 \frac{4}{15} = 3.26$

2)

$1 \frac{5}{6} \div ( \frac{2}{3} - \frac{3}{7} ) = \frac{11}{6} \times \frac{21}{5} = \frac{11}{2} \times \frac{7}{5} = \frac{77}{10} = 7 \frac{7}{10} = 7.7$

3)

$2 \frac{1}{3} \div ( \frac{5}{8} - \frac{8}{3} ) - 2 \times 1 \frac{3}{7} = \frac{7}{3} \div ( - \frac{49}{24} ) - \frac{6}{7} = - \frac{8}{7} - \frac{6}{7} = - 2$

4)-190+39-34+23549÷(84-91)=-185+23549÷(-7)=-24844/7=-3549 1/7