The common difference of an AP is -2. Find its sum , if first term is 100 and last term is -10.

The common difference of an AP is -2. Find its sum , if first term is

1.	The common difference of an AP is -2. Find its sum , if first term is 100 and last term is -10.
Answer» n=56 & Sn=5320 n=45 Sn=2025