Question

3. A store is trying out a new self-checkout system. They have had complaints from customers about errors in pricing in the new system, so the store runs a sample check. Out of 800 scanned items, they identify 24 items that had the wrong price entered through the self-checkout system.

(a) What is the estimate of the population proportion of errors in the new self check-out system? (2 points)

(b) Their old system had an error rate of 0.04 or 4 percent. Is this new system an improvement? Use the information provided to run a hypothesis test to answer this question. Clearly specify the null and alternative hypotheses, show each step of your work for either a critical value approach or a p-value approach, and clearly state the conclusion of the test. If you use Excel for any step of your analysis, you should still write down any formulas or equations used. Assume a significance level of 5 percent for your hypothesis test. (10 points)

Answer 1