Odds in Probability of Green Eyes

AI Thread Summary
In a class of 27 students, the probability of selecting exactly one student with green eyes when choosing three students is calculated. Initially, the odds were incorrectly determined as 92/883, but further analysis revealed that there are three different ways to select one green-eyed student. This adjustment leads to the correct probability of success being 276/975. Consequently, the odds of selecting one student with green eyes are accurately calculated as 92/233. The final conclusion confirms the book's answer as correct.
Math Man900
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Homework Statement


Of 27 students in a class, 11 have blue eyes, 13 have brown eyes, 3 have green eyes. If 3 students are chosen at random what are the odds of the following occurring?

Only 1 has green eyes.

Homework Equations


Odds = P( s )/P( f ) = P( s )/( 1 - P( s ))
Probability success = P( s )
Probability fail = P( f )

The Attempt at a Solution



P( s ) = (3/27) * (24/26) * (23/25) = 92/975
P( f ) = 1 - P( s ) = 883/975
Therefore: Odds = 92/883
I went over this problems many many times, and i believe this is the correct answer, but the back of the book says the answer is 92/233. There is a chance the back of the book is wrong. any ideas? thanks a lot.
 
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Nevermind. there are 3 ways to get 1 green person (1st,2nd, or 3rd) which means P( s ) = 3*92/975. and when you work out P( f ) you find the odds are: 92/233. QED. thanks
 
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