The monthly incomes from a random sample of workers in a factory are shown below: 18,14,12,14,12...

The monthly incomes from a random sample of workers in a factory are shown below:

18,14,12,14,12

a. Compute the margin of error (in dollars) at 98% confidence

b. Compute a 98% confidence interval for the mean of the population. Assume the population has a normal distribution. Give your answer in dollars.

Expert Solution

a)

sample mean x=	14.000
sample size n=	5
sample std deviation s=	2.449
std error sx=s/√n=	1.0954

for 98% CI; and 4 df, critical t=		3.7470
*margin of error E=tstd error =**		4.10

b)

lower bound=sample mean-E =		9.90
Upper bound=sample mean+E=		18.10

orchestra answered 3 years ago

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