Question
2a.A survey is conducted to estimate the average age of students enrolled in a college. The...
2a.A survey is conducted to estimate the average age of students
enrolled in a college. The population standard deviation is known
to be 2.5 years. 32 students were interviewed and their average age
was 22.6 years. For question 6, give the lowest
value of the 99% confidence interval of the population
mean (rounded to the tenths place). For question 7, refer back to
this question and give the highest value of the
99% confidence interval of the population mean. You will be using
the z-tables for this question.
2b.Give your answer for the highest value of the
99% confidence interval of the population mean (refer to question
2a), round your answer to the tenths place.
Homework Answers
Answer #1
We need to construct the 99% confidence interval for the population mean \muμ. The following information is provided:
| Sample Mean | 22.6 |
| Population Standard Deviation | 2.5 |
| Sample Size | 32 |
The critical value for α=0.01 is z_c =2.576. The corresponding confidence interval is computed as shown below:
CI = (21.462, 23.738)
Give the lowest value of the 99% confidence interval of the population mean (rounded to the tenths place).
21.5 years
Give the highest value of the 99% confidence interval of the population mean.
23.7 years
Give your answer for the highest value of the 99% confidence interval of the population mean (refer to question 2a), round your answer to the tenths place.
23.7 years
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