winmonkeyspit3
winmonkeyspit3
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February 17th, 2012 at 8:57:54 PM permalink
My university holds a Bingo event each semester where students have the opportunity to win an array of prizes ranging from ipods to sports tickets to even laptops and spring break vacation trips. I attended the event with my cross country team, which consists of 18 guys. According to the host, there were 1500-1600 people at the event. There were 30 rounds of Bingo, and out of these 30 rounds our group of 18 had 4 winners (myself included, winning an Xbox!) Even more crazy, three of us were sitting next to each other. Anybody know the probabilities of these events, I am still shocked at how unlikely this must have been statistically speaking.
s2dbaker
s2dbaker
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February 17th, 2012 at 9:19:41 PM permalink
I'm sure MathExtremist will correct me but here's what I came up with.

18 people out of 1600 is a 98.875% chance of not winning a single round. There were 30 rounds, divide by 4 since your group won four times so you would have to win once every, let's round it to 8 games. Chances of not winning in 8 games for your group is roughly 91.35% or 8.65% chance of winning. Chances of that happening 4 times in a row is quite small, like .0056% or about 1 chance in 18,000.
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winmonkeyspit3
winmonkeyspit3
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February 17th, 2012 at 9:45:04 PM permalink
Quote: s2dbaker

I'm sure MathExtremist will correct me but here's what I came up with.

18 people out of 1600 is a 98.875% chance of not winning a single round. There were 30 rounds, divide by 4 since your group won four times so you would have to win once every, let's round it to 8 games. Chances of not winning in 8 games for your group is roughly 91.35% or 8.65% chance of winning. Chances of that happening 4 times in a row is quite small, like .0056% or about 1 chance in 18,000.



Wow! Thanks for the math, I actually took discrete probability last semester but I'm an accounting guy so it's tough for me. Our group brought home an Ipad, Xbox, $100 itunes giftcard and package of DVD's. I guess that's why we pay $52,000 a year for college, but that's a whole different debate. Still pretty excited to see that happen though, I would say I should buy a Powerball ticket, but I've tried that before and it just doesn't work.
Wizard
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Wizard
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February 18th, 2012 at 3:16:27 AM permalink
combin(30,4)*(18/1600)^4*(1-(18/1600))^26 = 0.0003271.
"For with much wisdom comes much sorrow." -- Ecclesiastes 1:18 (NIV)
winmonkeyspit3
winmonkeyspit3
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February 19th, 2012 at 11:25:55 PM permalink
Quote: Wizard

combin(30,4)*(18/1600)^4*(1-(18/1600))^26 = 0.0003271.



Thanks Wizard! Wow! That calculation reminds me too much of my discrete probability final, I think i'll stick to the accounting. I'm going to try to sell the x-box on Ebay or my campus forum, add a little bit of money to my bankroll for blackjack. Thanks for the math!
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