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Glen_b
Glen_b
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Here is the Question:

For the genetics of a given plant, the probability of any seed it produces being brown is 3/4. The plant produces 80 seeds. Let X be the random variable that counts the number of brown seeds. Find the expected value and the standard deviation of X.

For the genetics of a given plant, the probability of any seed it produces being brown is 3/4. The plant produces 80 seeds. Let $X$ be the random variable that counts the number of brown seeds. Find the expected value and the standard deviation of $X$.

So... I figured the expected value of X$X$ to be 80 x 3/4 = 60. But what I don't understand is how do you figure the standard deviation of X$X$ when you have a brown seed or not! How do you get a mean from this?!

Here is the Question:

For the genetics of a given plant, the probability of any seed it produces being brown is 3/4. The plant produces 80 seeds. Let X be the random variable that counts the number of brown seeds. Find the expected value and the standard deviation of X.

So... I figured the expected value of X to be 80 x 3/4 = 60. But what I don't understand is how do you figure the standard deviation of X when you have a brown seed or not! How do you get a mean from this?!

For the genetics of a given plant, the probability of any seed it produces being brown is 3/4. The plant produces 80 seeds. Let $X$ be the random variable that counts the number of brown seeds. Find the expected value and the standard deviation of $X$.

So... I figured the expected value of $X$ to be 80 x 3/4 = 60. But what I don't understand is how do you figure the standard deviation of $X$ when you have a brown seed or not! How do you get a mean from this?

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Linny
Linny
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Standard Deviation

Here is the Question:

For the genetics of a given plant, the probability of any seed it produces being brown is 3/4. The plant produces 80 seeds. Let X be the random variable that counts the number of brown seeds. Find the expected value and the standard deviation of X.

So... I figured the expected value of X to be 80 x 3/4 = 60. But what I don't understand is how do you figure the standard deviation of X when you have a brown seed or not! How do you get a mean from this?!