A bag contains 4 green and 8 white balls

A bag contains 4 green and 8 white balls. If two balls are drawn simultaneously, the probability that both are of the same colour 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 #14089