SOLUTION: A school is sending 11 children to a camp. If 20% of the children in the school are first graders, and the 8 children are selected at random, what is the mean and variance of the

Question 896211: A school is sending 11 children to a camp. If 20% of the children in the school are first graders, and the 8 children are selected at random, what is the mean and variance of the number of first graders chosen?

Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
A school is sending 11 children to a camp. If 20% of the children in the school are first graders, and the 8 children are selected at random, what is the mean and variance of the number of first graders chosen?
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Binomial Problem:
mean = np = 11*0.2 = 2.2
variance = pq/n = (0.2*0.8)/8 = 0.16/8 = 0.2
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Cheers,
Stan H.
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