Вычислите: а) \(2\frac{2}{7}\times2,4\times1\frac{5}{9}\times\frac{9}{16}\); б) \(\frac{1}{3}\times1,125\times1\frac{5}{7}\times1\frac{9}{7}\).

а) \(2\frac{2}{7}=\frac{16}{7}\), \(2,4=\frac{12}{5}\), \(1\frac{5}{9}=\frac{14}{9}\). Тогда

\[\frac{16}{7}\cdot\frac{12}{5}\cdot\frac{14}{9}\cdot\frac{9}{16}=\frac{168}{5}=33,6.\]

б) \(1,125=\frac{9}{8}\), \(1\frac{5}{7}=\frac{12}{7}\), \(1\frac{9}{7}=\frac{16}{7}\). Тогда

\[\frac13\cdot\frac98\cdot\frac{12}{7}\cdot\frac{16}{7}=\frac{72}{49}=1\frac{23}{49}.\]

Ответ: а) 33,6; б) \(1\frac{23}{49}\).