SOLUTION: The question reads: A university has 10,000 students of which 4,000 are male and 6,000 are female. If a class of 30 students is chosen at random from the university population, f

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Question 441087: The question reads: A university has 10,000 students of which 4,000 are male and 6,000 are female. If a class of 30 students is chosen at random from the university population, find the mean and standard deviation of the number of male students.
After using the formula for binomial distribution mean (np) and standard deviation (square root of np(1-p), I came up with the answer...
mean= 12
standard deviation = 2.68
I am confused when to use which equation so I was hoping you could verify my answer. Thank you!

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
The question reads: A university has 10,000 students of which 4,000 are male and 6,000 are female. If a class of 30 students is chosen at random from the university population, find the mean and standard deviation of the number of male students.
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P(male) = 4/10 = 2/5
n = 30
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mean = np = (2/5)30 = 12
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std = sqrt(npq) = sqrt(12*(3/5)) = 2.6833
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I agree with your answers.
Cheers,
Stan H.
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After using the formula for binomial distribution mean (np) and standard deviation (square root of np(1-p), I came up with the answer...
mean= 12
standard deviation = 2.68
I am confused when to use which equation so I was hoping you could verify my answer.