1. Вычислите \( \frac{3}{8} \cdot \left( \frac{7}{8} + \frac{15}{24} \right) \).

\( \frac{3}{8} \cdot \left( \frac{7}{8} + \frac{15}{24} \right) = \frac{3}{8} \cdot \left( \frac{21}{24} + \frac{15}{24} \right) = \frac{3}{8} \cdot \frac{36}{24} = \frac{3}{8} \cdot \frac{3}{2} = \frac{9}{16} \). Ответ: \( \frac{9}{16} \).