1. Решите уравнение: 1) 6 : 5 = x: 75 2) a:1\frac{7}{50}=\frac{5}{57}:\frac{1}{2} 3)\frac{x}{0,8}=\frac{15}{4} 4)\frac{5-y}{4}=\frac{3}{7}

1. Решите уравнение:

1) $$6:5 = x : 75$$

$$x = \frac{6 \cdot 75}{5}$$

$$x = \frac{6 \cdot 15}{1}$$

$$x = 90$$

Ответ: x = 90

2) $$a:1\frac{7}{50}=\frac{5}{57}:\frac{1}{2}$$

$$a:\frac{57}{50} = \frac{5}{57}:\frac{1}{2}$$

$$a:\frac{57}{50} = \frac{5 \cdot 2}{57}$$

$$a = \frac{10}{57} \cdot \frac{57}{50}$$

$$a = \frac{10}{50}$$

$$a = \frac{1}{5}$$

Ответ: a = 1/5

3) $$\frac{x}{0,8} = \frac{15}{4}$$

$$x = \frac{15 \cdot 0,8}{4}$$

$$x = \frac{15 \cdot 0,2}{1}$$

$$x = 3$$

Ответ: x = 3

4) $$\frac{5-y}{4} = \frac{3}{7}$$

$$5-y = \frac{3 \cdot 4}{7}$$

$$5-y = \frac{12}{7}$$

$$y = 5 - \frac{12}{7}$$

$$y = \frac{35}{7} - \frac{12}{7}$$

$$y = \frac{23}{7}$$

$$y = 3\frac{2}{7}$$

Ответ: y = 3 2/7