Question

............... Решите пожалуйста​

Answer 1

Объяснение:

7.

$\frac{0.9}{1 + \frac{1 }{8} } = \frac{0.9}{1 \frac{1}{8} } = \frac{0.9}{ \frac{9}{8} } = \frac{9}{10} \times \frac{8}{9} = \frac{8}{10} = \frac{4}{5}$

8.

$\frac{27}{5 \times 4} = \frac{27}{20} = 1 \frac{7}{20}$

9.

$(2 \frac{3}{4} + 2 \frac{1}{5} ) \times 16 = (2 \frac{15}{20} + 2 \frac{4}{20}) \times 16 =4 \frac{19}{20} \times 16 = \frac{99}{20} \times 16 = \frac{99}{5} \times 4 = \frac{396}{5}$

10.

$\frac{24}{3.2 \times 2} = \frac{12}{3.2} = \frac{12}{3 \frac{1}{5} } = \frac{12}{1} \div \frac{16}{5} = 12 \times \frac{5}{16} = 3 \times \frac{5}{4} = \frac{15}{4}$

11.

$1 \frac{8}{17} \div ( \frac{12}{17} + 2 \frac{7}{11} ) = \frac{25}{17} \div ( \frac{12}{17} + \frac{29}{11} ) = \frac{25}{17} \div ( \frac{132 + 493}{187} ) = \frac{25}{17} \div \frac{625}{187} = \frac{25}{17} \times \frac{187}{625} = \frac{11}{25}$

12.

$\frac{1}{4} + 0.7 = 0.25 + 0.7 = 0.95$

13.

$\frac{1}{ \frac{1}{18} - \frac{1}{21} } = \frac{1}{ \frac{7 - 6}{126} } = \frac{1}{ \frac{1}{126} } = 1 \div \frac{1}{126} = 1 \times \frac{126}{1} = 126$

14.

$\frac{9}{5} \times \frac{2}{3} = \frac{3 \times 2}{5} = \frac{6}{5} = 1.2$