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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Guest Message by DevFuse

Started by Writersblock, Jan 23 2008 07:45 PM

5 replies to this topic

### #1

Posted 23 January 2008 - 07:45 PM

### #2

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."

"Do or do not; there is no try."

### #3

Posted 23 January 2008 - 09:11 PM

Spoiler for Here are my thoughts

*The greatest challenge to any thinker is stating the problem in a way that will allow a solution.*

- Bertrand Russell

### #4

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 ...

### #5

Posted 23 January 2008 - 11:27 PM

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

Spoiler for ...

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 )

### #6

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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