\(\left(1-\dfrac{1}{2}\right)\times\left(1-\dfrac{1}{3}\right)\times\left(1-\dfrac{1}{4}\right)\times\left(1-\dfrac{1}{6}\right)\times\left(1-\dfrac{1}{6}\right)\)
\(=\dfrac{1}{2}\times\dfrac{2}{3}\times\dfrac{3}{4}\times\dfrac{4}{5}\times\dfrac{5}{6}\)
\(=\dfrac{1\times2\times3\times4\times5}{2\times3\times4\times5\times6}\)
\(=\dfrac{1}{6}\)