9 Реши уравнение: a) 14/x = 30; 80/y = 5; m/28 = 36; 513/n = 19; б) (a+3 4/7)-1 1/2 = 4 3/7; (2 19/23)-(5/23 + b) = 1 6/23; (c-2 3/11)+5 1/11 = 7; 3 3/4 + (8-d) = 6 9/5.

Решим уравнения:

a) $$\frac{14}{x} = 30$$

$$x = \frac{14}{30} = \frac{7}{15}$$

Ответ: $$\frac{7}{15}$$

$$\frac{80}{y} = 5$$

$$y = \frac{80}{5} = 16$$

Ответ: 16

$$\frac{m}{28} = 36$$

$$m = 28 \cdot 36 = 1008$$

Ответ: 1008

$$\frac{513}{n} = 19$$

$$n = \frac{513}{19} = 27$$

Ответ: 27

б) $$(a+3\frac{4}{7})-1\frac{1}{2} = 4\frac{3}{7}$$

$$a+3\frac{4}{7} = 4\frac{3}{7} + 1\frac{1}{2}$$

$$a+3\frac{4}{7} = 4\frac{6}{14} + 1\frac{7}{14}$$

$$a+3\frac{4}{7} = 5\frac{13}{14}$$

$$a = 5\frac{13}{14} - 3\frac{4}{7}$$

$$a = 5\frac{13}{14} - 3\frac{8}{14}$$

$$a = 2\frac{5}{14}$$

Ответ: $$2\frac{5}{14}$$

$$(2\frac{19}{23})-(\frac{5}{23} + b) = 1\frac{6}{23}$$

$$\frac{5}{23} + b = 2\frac{19}{23} - 1\frac{6}{23}$$

$$\frac{5}{23} + b = 1\frac{13}{23}$$

$$b = 1\frac{13}{23} - \frac{5}{23}$$

$$b = 1\frac{8}{23}$$

Ответ: $$1\frac{8}{23}$$

$$(c-2\frac{3}{11})+5\frac{1}{11} = 7$$

$$c-2\frac{3}{11} = 7 - 5\frac{1}{11}$$

$$c-2\frac{3}{11} = 1\frac{10}{11}$$

$$c = 1\frac{10}{11} + 2\frac{3}{11}$$

$$c = 3\frac{13}{11} = 4\frac{2}{11}$$

Ответ: $$4\frac{2}{11}$$

$$3\frac{3}{4} + (8-d) = 6\frac{9}{5}$$

$$8-d = 6\frac{9}{5} - 3\frac{3}{4}$$

$$8-d = 6\frac{36}{20} - 3\frac{15}{20}$$

$$8-d = 3\frac{21}{20} = 4\frac{1}{20}$$

$$d = 8 - 4\frac{1}{20}$$

$$d = 7\frac{20}{20} - 4\frac{1}{20}$$

$$d = 3\frac{19}{20}$$

Ответ: $$3\frac{19}{20}$$