4.338 Решите уравнение: a) 1 3/4 : 3,75 = 4x : 15;

a) \(1 \frac{3}{4} : 3,75 = 4x : 15\). \(\frac{7}{4} : \frac{15}{4} = \frac{4x}{15}\). \(\frac{7}{4} \cdot \frac{4}{15} = \frac{4x}{15}\). \(\frac{7}{15} = \frac{4x}{15}\). \(7 = 4x\). \(x = \frac{7}{4} = 1 \frac{3}{4}\). Ответ: \(x = 1 \frac{3}{4}\)