Probability

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carllecat
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Topic: Probability
PostTue Nov 17, 2009 9:18 am
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In a certain board game, a stack of 48 cards, 8 of which represent shares of stock, are shuffled and then placed face down. If the first 2 cards selected do not represent shares of stock, what is the probability that the third card selected will represent a share of stock?

A) 1/8
B) 1/6
C) 1/5
D) 3/23
E) 4/23

Answer to be posted later.
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carllecat
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PostTue Nov 17, 2009 9:48 am
E) 4/23
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carllecat
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PostThu Nov 19, 2009 8:20 am
Anyone?
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mp2437
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PostThu Nov 19, 2009 8:57 am
You have 48 cards, 8 of which are shares. You remove 2, of which none are shares, so you still have 8 cards in the stack that are shares, but since you removed 2, you now have 48 - 2 = 46 cards. The probabilty that the next card will be a share is 8 / 46, or simplified, 4/23. Choice E.
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carllecat
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PostThu Nov 19, 2009 10:56 am
mp2437 wrote:
You have 48 cards, 8 of which are shares. You remove 2, of which none are shares, so you still have 8 cards in the stack that are shares, but since you removed 2, you now have 48 - 2 = 46 cards. The probabilty that the next card will be a share is 8 / 46, or simplified, 4/23. Choice E.
I was just trying too hard... Thanks!
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