Find the sum of the first 9 prime numbers.
A prime number is a positive integer that has exactly two positive integer factors: 1 and itself. The first 9 prime numbers are 2, 3, 5, 7, 11, 13, 17, 19, and 23. I enter 2 + 3 + 5 + 7 + 11 + 13 + 17 + 19 + 23 and press equals. I get 100 as the answer. 