Question

What is the sum of the first 20 positive integers?

Answer 1

The formula for the sum of the first `n` integers is:

`(n(n + 1))/2`

Substituting `20` for `n` and evaluating the expression gives:

`(20(20 + 1))/2 => (20 * 21)/2 = 420/2 = 210`