Question

In: Statistics and Probability

Consider a population having a standard deviation equal to 9.81. We wish to estimate the mean...

Consider a population having a standard deviation equal to 9.81. We wish to estimate the mean of this population.

(a) How large a random sample is needed to construct a 95 percent confidence interval for the mean of this population with a margin of error equal to 1? (Round answer to the next whole number.)

The random sample is _________ units.

(b) Suppose that we now take a random sample of the size we have determined in part a. If we obtain a sample mean equal to 276, calculate the 95 percent confidence interval for the population mean. What is the interval’s margin of error? (Round answer to the nearest whole number.)

The 95 percent confidence interval is [, ] .

Margin of error _________

Expert Solution

a)

alpha = 1-0.95=0.05

b)

margin of error =

confidence interval=

orchestra answered 1 year ago

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