\(=\dfrac{16}{9}\cdot\dfrac{27}{20}\cdot\dfrac{40}{33}\cdot\dfrac{55}{48}\cdot\dfrac{75}{65}\cdot\dfrac{91}{84}\)
\(=\dfrac{16}{84}\cdot3\cdot2\cdot\dfrac{5}{3}\cdot\dfrac{25}{16}\cdot\dfrac{7}{5}\)
\(=\dfrac{4}{21}\cdot2\cdot5\cdot\dfrac{35}{16}\)
\(=\dfrac{4}{16}\cdot\dfrac{35}{21}\cdot10=\dfrac{1}{4}\cdot10\cdot\dfrac{5}{3}=\dfrac{50}{3}\cdot\dfrac{1}{4}=\dfrac{50}{12}=\dfrac{25}{6}\)

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