1.)The ages of millionaires in a city are normally distributed with a population standard deviation of...

1.)The ages of millionaires in a city are normally distributed with a population standard deviation of 3 years and an unknown population mean. A random sample of 23 millionaires is taken and results in a sample mean of 44 years.

Find the margin of error for a 95% confidence interval for the population mean.

z0.10z0.10	z0.05z0.05	z0.025z0.025	z0.01z0.01	z0.005z0.005
1.282	1.645	1.960	2.326	2.576

You may use a calculator or the common z values above.

Round the final answer to two decimal places.

2.) A college admissions director wishes to estimate the mean age of all students currently enrolled. The age of a random sample of 23 students is given below. Assume the ages are approximately normally distributed. Use Excel to construct a 90% confidence interval for the population mean age. Round your answers to two decimal places and use increasing order

Age
25.8
22.2
22.5
22.8
24.6
24.0
22.6
23.6
22.8
23.1
21.5
21.4
22.5
24.5
21.5
22.5
20.5
23.0
25.1
25.2
23.8
21.8
24.1

Expert Solution

orchestra answered 1 year ago

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