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Ifor example, if two coins are flipped the chance of both being heads is [18]

Mutually exclusive If either event A or event B or both events occur on a single performance of an experiment this is called the union of the events A and B denoted as .

For example, the chance of rolling a 1 or 2 on a six-sided die is

This is from Wikipedia. I found this when I was searching for the explanation for this question. But I am still confused the difference between independent probability and mutually exclusive. To me, they sound the same. Help me understand them.

Re: What is the probability that event E or event F or both will [#permalink]
14 Jan 2014, 01:39

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Re: What is the probability that event E or event F or both will [#permalink]
28 Jan 2014, 04:22

1

This post received KUDOS

Mountain14 wrote:

Hi Bunuel,

I am not clear why E is the answer...

we have to find P(E)+P(F) + P(EUF), so using Stm1 and Stm 2, we should be able to find.

i.e 0.6 +0.4 + ( 0.6x0.4)...

So, Isn't the answer should be C

Thanks

I'm not Bunuel but I'm sure I can help

P (A and B) = P(A) * P (B/A). That means the probability of B given that A happens. Now only way that the second term is equal to P(B) is if they are independent events, otherwise the probability will be affected. For instance if you have some balls to pick from and you remove some and don't replace them then successive probabilities will change right? So back to the question, Are they independent events? We just don't know this.

Hope it helps brother Cheers! K

PS. Just as a side note check also Mutually exclusive events in the GMAT Club Math Book just to be clear with those Probability concepts

Re: What is the probability that event E or event F or both will [#permalink]
28 Jan 2014, 05:34

Hi we have no information weather E and F are independent events. So we cant answer the question even by considering the two choices So ans should be E

gmatclubot

Re: What is the probability that event E or event F or both will
[#permalink]
28 Jan 2014, 05:34