20 Вычислите: rac{11}{72} : (rac{7}{24} + rac{9}{32})

1. НОК(24, 32) = 96. 2. rac{7}{24} + rac{9}{32} = rac{7 · 4}{96} + rac{9 · 3}{96} = rac{28+27}{96} = rac{55}{96}. 3. rac{11}{72} : rac{55}{96} = rac{11}{72} · rac{96}{55} = rac{1056}{3960} = rac{4}{15}