Question:
If $[x]$ be the greatest integer less than or equal to $x$,
then $\sum_{n=8}^{100}\left[\frac{(-1)^{n} n}{2}\right]$ is equal to:
Correct Option: , 2
Solution:
$\sum_{n=8}^{100}\left[\frac{(-1)^{n} \cdot n}{2}\right]$
$=4-5+5-6+6+\ldots-50+50=4$