(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

If there are 4 children in a family, find the probability of getting exactly 3 girls. Find the mean, variance, and standard deviation. Use two different methods(binomial distribution method and general probability distribution method).

2. Relevant equations

Binomial distribution equations:

Mean=np

variance=npq

standard deviation= sq. root of variance

3. The attempt at a solution

mean= (4)(.75)=3

variance=(4)(.75)(.25)=.75

s.d.= .866

is that right?

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# Homework Help: Find the mean, variance, and standard deviation

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