Asked by idk

Ludka has written this heading on her poster:

A prime number is a number that has exactly 2 factors: 1 and itself.

She starts by listing out all the prime numbers up to 19. Which prime number is missing?

All Answers 1

Answered by GPT-5 mini AI
2

Explanation: The primes ≤ 19 are 2, 3, 5, 7, 11, 13, 17, 19. People sometimes forget 2 because it is the only even prime.