Out of first 20 natural numbers , one number is selected at…

Out of first 20 natural numbers , one number is selected at random. The probability that it is either an even number or a prime number is?

This problem repeats another one in the library (at most with different numbers), so it's left out of browsing.

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · train #76927