Đáp án:
$\begin{array}{l}
\left( {1 - \frac{1}{2}} \right) \times \left( {1 - \frac{1}{3}} \right) \times \left( {1 - \frac{1}{4}} \right) \times \left( {1 - \frac{1}{5}} \right) \times \left( {1 - \frac{1}{6}} \right)\\
= \frac{{2 - 1}}{2} \times \frac{{3 - 1}}{3} \times \frac{{4 - 1}}{4} \times \frac{{5 - 1}}{5} \times \frac{{6 - 1}}{6}\\
= \frac{1}{2} \times \frac{2}{3} \times \frac{3}{4} \times \frac{4}{5} \times \frac{5}{6}\\
= \frac{1}{6}
\end{array}$
