4.338 Решите уравнение: а) 1\frac{3}{4} : 3,75 = 4x : 15; 6) \frac{1}{2}: 13 = \frac{3}{3}x : 4\frac{1}{3}.

a) $$1\frac{3}{4} : 3,75 = 4x : 15$$

$$\frac{7}{4} : \frac{15}{4} = 4x : 15$$

$$\frac{7}{4} \cdot \frac{4}{15} = 4x : 15$$

$$\frac{7}{15} = 4x : 15$$

$$\frac{7}{15} = \frac{4x}{15}$$

$$4x = 7$$

$$x = \frac{7}{4} = 1,75$$

б) $$\frac{1}{2}: 13 = \frac{3}{3}x : 4\frac{1}{3}$$

$$\frac{1}{26} = \frac{4}{3}x : \frac{13}{3}$$

$$\frac{1}{26} = \frac{4}{3}x \cdot \frac{3}{13}$$

$$\frac{1}{26} = \frac{4x}{13}$$

$$4x = \frac{13}{26}$$

$$4x = \frac{1}{2}$$

$$x = \frac{1}{8} = 0,125$$

Ответ: а) x = 1,75; б) x = 0,125