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Probabilit - basket of apples

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Re: Probabilit - basket of apples

by dtweah » Mon May 18, 2009 12:55 pm
crackgmat007 wrote:Can someone solve this pls?
(4C1 x 1C1)/5C2=2/5
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by artistocrat » Mon May 18, 2009 2:35 pm
Spoiled=S
Not spoiled=N

So outcomes are S,N and N,S

S,N: 1/5*4/4=1/5
N,S: 4/5*1/4=1/5

So total number of favorable outcomes=1/5+1/5=2/5
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by mike22629 » Tue May 19, 2009 8:23 am
For these "at least" probability questions, it is generally best to use the
"1-x" method

First:
Find total number of possibilities = 5C2

(5!)/(2!*3!) = 10

Second:
Find total number of possibilities when he does NOT choose the spoiled apple = (4!/(2!*2!) = 6

Hence Probability of not choosing it is 3/5

1 - (3/5) = Probability of choosing it = 2/5
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