Can Sal predict the ratio of white to black balls without looking at all of them? Created by Brit Cruise.
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- What happens if you do not put the beads back?(5 votes)
- sal said the more trials, the more he will get close to the right path, is that true?(6 votes)
- I am confused what is going since there basically picking balls the whole time and sal is trying to guess the ratio.(1 vote)
- I think sal is wrong because he said that the more trials the more likely he is going to get it correct, is that true?(0 votes)
- No, he is correct. See the next video. The results in the video were caused by pure chance.(2 votes)
- way do's the video not work?(0 votes)
- It depends if your teacher probably blocked the videos since they are uploaded on youtube. It happens to me to when i use the school computers.(1 vote)
- Does the 'combination selected', so in the case, 'the balls' - must they be returned to the cup to be classified as random sampling?(0 votes)
- Yes, or else once you take all of the balls out you'll know the exact number which won't be random sampling.(1 vote)
- [Brit] Hey Sal. - [Sal] Hello Brit. - I have a challenge for you, 'cause I heard you have some kind of predictive powers, you're a bit of a magician. (Marbles Rattle) - There might be some truths to that, limited truth. (Laughing) - [Brit] I want to test it out. What I did was I filled this black bucket with a certain number of white and black beads. And I know what you're gonna say, I'm gonna prove to you that I have both white and black. - Okay. - So here's the white. - White. - No tricky business here, I'm a bit of a magician myself. - Math magician. - Math magician. And here's the dark. - Dark. - So they both exist. Now I'm wondering, you can touch it, you could do whatever you want, but you can't look inside of it. You can touch it. - I should scratch it. - Yeah, yeah, whatever you wanna do. - Tickle it. - Is there more white or black? That's my first question. Could you just guess of there's more or less and could you tell me - I refuse to guess. - [Brit] You won't even play? - 'cause I don't know, you just showed me two mar- I know there's at least one white and at least one black. - But I don't want to show you what's in here, so what- - So can I take some out? - Can I do it? - How about I do it? 'cause I think you might know the marbles or you might be looking in the thing when you pick it out. - Okay. - I want it to be randomly selected. - [Sal] Black. So can I do it again? - You can do it again. But we're gonna put the bead back in. - Okay, no, that's fair. (marbles rattle) - [Sal] Okay my eyes are closed. White. - [Sal] This is fascinating. So in 10 tries, I got five black and I got five whites. So, once again, I wouldn't bet my life savings on this, because once again, this might have been just the way I happen to pick it. But if I had to guess, I would say that you have an equal number of white and black. - So that's your guess and your ratio? - Well I would say one to one, for every white there's a black. I would guess whatever, half of those are white and half of those are black. Now, I could very well be wrong. Okay, show us what's going on. - I got you there. We have two and four. - Oh. So the correct one is, wow I had two whites for every black. The ratio was 2:1. - So at the beginning, you were actually very close. - I was spot on in the beginning. - And that's why I think the more trials, perhaps less likely that you're gonna get it correct. - I disagree with that. I disagree with that. I think that the more trials, it just happened in that it kind of took me off the right path this time. But I think if I did that more times than not, it would get me closer to the right answer.