The value of $\left(1-\frac{1}{2}\right)\left(1-\frac{1}{3}\right)\left(1-\frac{1}{4}\right).........\left(1-\frac{1}{n}\right)$ is -

Explanation

$\left(1-\frac{1}{2}\right)\left(1-\frac{1}{3}\right)\left(1-\frac{1}{4}\right).........\left(1-\frac{1}{n}\right)$ $= \frac{1}{2} \times \frac{2}{3} \times \frac{3}{4} ........... \frac{n-1}{n} = \frac{1}{n}$