If 4 people are selected from a group of 9 married couples…

If 4 people are selected from a group of 9 married couples, what is the probability that none of them would be married to each other?

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 #18785