Question

7. An economist wants to estimate the mean per capita income (in thousands of dollars) for a major city in California. Suppose that the mean income is found to be $25.8 for a random sample of 2323 people. Assume the population standard deviation is known to be $9. Construct the 98% confidence interval for the mean per capita income in thousands of dollars. Round your answers to one decimal place.

Lower endpoint:

Upper endpoint:

8. Consider the value of t such that 0.05 of the area under the curve is to the right of t.

Step 1 of 2: Select the graph which best represents the given description of t.

Step 2 of 2: Assuming the degrees of freedom equals 1616, select the t value from the t table.

Answer 1

Lower endpoint = 21.43

Upper endpoint = 30.17