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### #1 Writersblock

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Posted 23 January 2008 - 07:45 PM

I heard this on Leno last night and thought it made a decent teaser.

A new energy company does a survey on how many people carpool. What are the odds that exactly 3 out of 4 people fail to carpool?
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### #2 Jkyle1980

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Posted 23 January 2008 - 09:04 PM

The odds of 3 of 4 people failing to carpool is either 0 or 1. Jay is asking the odds of a a certain probability. What are the odds that the chances of rolling a 6 on one roll with one die is 1/6? The carpool ratio, as well as the die roll ratio, is already set so it either is or it isn't 3 of 4 fail.

"Do or do not; there is no try."
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### #3 bonanova

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Posted 23 January 2008 - 09:11 PM

Spoiler for Here are my thoughts

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Vidi vici veni.

### #4 Writersblock

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Posted 23 January 2008 - 11:00 PM

So if 3 out of 4 are not carpooling, who is the 4th guy riding with?

Spoiler for ...

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### #5 niner

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Posted 23 January 2008 - 11:27 PM

So if 3 out of 4 are not carpooling, who is the 4th guy riding with?

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I did think that; how could 1 person carpool? I didn't think it was a meaningful answer and did not submit it (though that hasn't stopped me before )
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### #6 Jkyle1980

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Posted 24 January 2008 - 12:23 AM

I've been working so many probability problems on here over the last week that I instantly see all fractions as percentages and not sets.
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