Need Quick Help on these !Example ? The household incomes in a metropolitan area have mean $36,400 and standard deviation $11,700. If a random sample

Need Quick Help on these !Example ? The household incomes in a metropolitan area have mean $36,400 and standard deviation $11,700. If a random sample of 400 households is drawn and its sample mean calculated, with what probability will the absolute sampling error exceed $500?Example ? How large a sample is needed above to have P(|X? ? ?| > 500) < 0.1?Example ? Of all such households, 22% have incomes below $18,000. For a random sample of 1500, what?s the probability that the proportion below $18,000 exceeds 23%?Example ? Incomes on the West side have mean ?1 and variance ? 2 1 , whereas those on the East side have mean ?2 and variance ? 2 2 . If the sample size n is split as n = n1 + n2 between West and East, what is the approximate distribution of the difference X? 1 ? X? 2?

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