Решение:
- \(\frac{9}{16} : (\frac{1}{4} + \frac{5}{12}) - \frac{8}{15} : \frac{16}{45} = \frac{9}{16} : (\frac{3}{12} + \frac{5}{12}) - \frac{8}{15} : \frac{16}{45} = \frac{9}{16} : \frac{8}{12} - \frac{8}{15} : \frac{16}{45} = \frac{9}{16} : \frac{2}{3} - \frac{8}{15} : \frac{16}{45} = \frac{9}{16} \cdot \frac{3}{2} - \frac{8}{15} \cdot \frac{45}{16} = \frac{27}{32} - \frac{1}{1} \cdot \frac{3}{2} = \frac{27}{32} - \frac{3}{2} = \frac{27}{32} - \frac{48}{32} = -\frac{21}{32}\)
Ответ: -\(\frac{21}{32}\)