It's a probability question. Let's say I had a box with 36 numbered b***s (9 red 9 blue 9 white 9 green) inside. And I had to pick 5 b***s from it. What are the odds that I'll get atleast 2 RED b***s?
I'm taking "odds" to mean "probability"
At least 2 red means : 2 red, 3 red,4 red or 5 red
There are C(36,5) possibilities
And for 2 red...we want to choose 2 of the 5 red and 3 of the other 31
Similarly...for 3 red, we want to choose 3 of the 5 red and 2 of the other 31, etc.
So we have
[ C(5,2)*C(31,3) + C(5,3)*C(31,2) + C(5,4)*C(31,1) + C(5,5)] / C(36,5) =
1777 / 13464 ≈ 13.2%
P.S. - the odds for this are 1777 to [13464 - 1777] = 1777 to 11687