203. Найдите значение выражения: а) \(2\frac{2}{3}:1\frac{7}{9}+\frac{55}{84}:\left(\frac{43}{63}-\frac{23}{36}\right)\); б) \(5\frac{5}{7}:\frac{8}{21}+1\frac{8}{13}\cdot\left(\frac{43}{56}-\frac{11}{24}\right)\).

а) \(2\frac{2}{3}:1\frac{7}{9}+\frac{55}{84}:\left(\frac{43}{63}-\frac{23}{36}\right)\)

\(\frac{8}{3}:\frac{16}{9}=\frac{3}{2}\).

\(\frac{43}{63}-\frac{23}{36}=\frac{172-161}{252}=\frac{11}{252}\).

\(\frac{55}{84}:\frac{11}{252}=15\).

\(\frac{3}{2}+15=\frac{33}{2}=16\frac{1}{2}\).

б) \(5\frac{5}{7}:\frac{8}{21}+1\frac{8}{13}\cdot\left(\frac{43}{56}-\frac{11}{24}\right)\)

\(\frac{40}{7}:\frac{8}{21}=15\).

\(\frac{43}{56}-\frac{11}{24}=\frac{129-77}{168}=\frac{13}{42}\).

\(\frac{21}{13}\cdot\frac{13}{42}=\frac{1}{2}\).

\(15+\frac{1}{2}=15\frac{1}{2}\).

Ответ: а) \(16\frac{1}{2}\); б) \(15\frac{1}{2}\).