6.1 Exercise
ninafukuma
Could someone explain why it is 12 choose 5, rather than 12 pick 5? Why doesn't the order matter for this question? I'm a bit confused about what the "ways" refer to.
eshiar: Jan. 26, 2015, 11:35 a.m.
If you did 12 pick 5, you are pretty much saying how each of the times you pick the green ball, it is different. But since the green ball is just the same ball over and over again, the order would not matter as the green ball would look the same as the green ball (it's the exact same ball). I hope this helped!
weisbart: Feb. 1, 2015, 11:12 a.m.
This is correct. Maybe this explanation will also help. You're just picking the trials when you will pick the ball. It does't matter if you pick the green ball on trial 1, trial 3, trial 4, trial 5, and trial 8, or if you pick the green ball on trial 4, trial 3, trial 8, trial 5, and trial 1. Does this make sense?