Question

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.

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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