K.Brew sells a wide variety of outdoor equipment and clothing. The company sells both in-store and online. Random samples of sales receipts were studied for in-store sales and online sales, with the total purchase being recorded for each sale. A random sample of 1010 sales receipts for in-store sales results in a mean sale amount of $75.80$75.80 with a standard deviation of $27.25$27.25. A random sample of 1414 sales receipts for online sales results in a mean sale amount of $83.40$83.40 with a standard deviation of $17.75$17.75. Using this data, find the 95%95% confidence interval for the true mean difference between the mean amount of in-store purchases and the mean amount of online purchases. Assume that the population variances are not equal and that the two populations are normally distributed. Step 1 of 3: Find the critical value that should be used in constructing the confidence interval. Round your answer to three decimal places. Step 2 of 3: Find the standard error of the sampling distribution to be used in constructing the confidence interval. Round your answer to two decimal places. Step 3 of 3: Construct the 95%95% confidence interval. Round your answers to two decimal places.
K.Brew sells a wide variety of outdoor equipment and clothing. The company sells both in-store and online. Random samples of sales receipts were studied for in-store sales and online sales, with the total purchase being recorded for each sale. A random sample of 1010 sales receipts for in-store sales results in a mean sale amount of $75.80$75.80 with a standard deviation of $27.25$27.25. A random sample of 1414 sales receipts for online sales results in a mean sale amount of $83.40$83.40 with a standard deviation of $17.75$17.75. Using this data, find the 95%95% confidence interval for the true mean difference between the mean amount of in-store purchases and the mean amount of online purchases. Assume that the population variances are not equal and that the two populations are
Find the critical value that should be used in constructing the confidence interval. Round your answer to three decimal places.
Find the standard error of the sampling distribution to be used in constructing the confidence interval. Round your answer to two decimal places.
Construct the 95%95% confidence interval. Round your answers to two decimal places.
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