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September 24, 2021, 01:42:17 pm

### AuthorTopic: Expected Value Probability  (Read 612 times) Tweet Share

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#### miaconway_05

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##### Expected Value Probability
« on: July 31, 2021, 10:02:50 pm »
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I've tried using the standard procedure of multiplying each outcome by 1/n and adding the results. Also I'm using an expected value table, with the rows 1,2 and 3 being x,p(x),xp(x). Any help would be appreciated! *the q is 3d

#### fun_jirachi

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##### Re: Expected Value Probability
« Reply #1 on: August 01, 2021, 12:52:29 am »
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The question implies you have a binomial distribution. The expected value for a binomial is $np$ where $p$ is the chance of 'success', and $n$ is the number of trials. Here, you want to find the expected number of faulty cars given 3 trials and the chance of 'success' being $\frac{1}{1000}$; hence, $E(X) = \frac{3}{1000}$.

Hope this helps
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