SOLUTION: find mean, variance, standard deviation of n= 120 and p= 0.4 also can u explain how you get that little extra number in the variance, im not understanding i get stuck there.

Algebra ->  Probability-and-statistics -> SOLUTION: find mean, variance, standard deviation of n= 120 and p= 0.4 also can u explain how you get that little extra number in the variance, im not understanding i get stuck there.      Log On


   

Question 483924: find mean, variance, standard deviation of n= 120 and p= 0.4
also can u explain how you get that little extra number in the variance, im not understanding i get stuck there.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
find mean, variance, standard deviation of
n= 120 and p= 0.4 and q = 0.6
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mean = np = 0.4*120 = 48
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std = sqrt(npq) = sqrt(48*0.6) = 5.3666..
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variance = npq = 48*0.6 = 28.8
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Cheers,
Stan H.
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