What is the sum of the first 100 positive integers?

Question

Accepted Answer

The positive integers form an AP: $1, 2, 3, ..., 100$ with $a = 1$, $d = 1$, and $n = 100$. Using the formula for the sum of $n$ terms $Sn = \frac{n(n + 1)}{2}$, we get $S{100} = \frac{100(100 + 1)}{2} = 50 	imes 101 = 5050$. Therefore, option C is correct.

Arithmetic Progressions

❓ Sibling Questions in this Chapter