Calculating the confidence interval using the given data

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1. A random sample of 100 stores from a large chain of 1,000 garden supply stores was selected to determine the average number of lawnmowers sold at an end-of-season clearance sale.  The sample results indicated an average of 6 and a standard deviation of 2 lawnmowers sold. Find the 95% confidence interval for the true population mean. Can we conclude that of all possible samples of 100 stores taken from the population of 1,000 stores, 95% of the confidence interval will contain the true population mean within the interval? Justify your answer.

2. A random sample of 10 observations is selected from the first normal population and 8 from the second normal population. For a two-tailed test of hypothesis (.01 significance level) to determine if there is a difference in the population means, the degrees of freedom are?

a) 18

b) 17

c) 16

d) None of the above

Reference no: EM1319866

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