Posted by **Sandy** on Saturday, February 23, 2013 at 11:33pm.

Accuracy of price scanners at Wal-Mart. The National Institute for Standards and Technology (NIST) mandates that for every 100 items scanned through the electronic checkout scanner at a retail store, no more than 2 should have an inaccurate price. A recent study of the accuracy of checkout scanners at Wal-Mart stores in California was conducted (Tampa Tribune, Nov. 22, 2005). At each of 60 randomly selected Wal-Mart stores, 100 random items were scanned. The researchers found that 52 of the 60 stores had more than 2 items that were inaccurately priced.

a. Give an estimate of p, the proportion of Wal-Mart stores in California that have more than 2 inaccurately priced items per 100 items scanned.

b. Construct a 95% confidence interval for p.

c. Give a practical interpretation of the interval, part b.

d. Suppose a Wal-Mart spokesperson claims that 99% of California Wal-Mart stores are in compliance with the NIST mandate on accuracy of price scanners. Comment on the believability of this claim.

e. Are the conditions required for a valid large-sample confidence interval for p satisfied in this application? If not, comment on the validity of the inference in part d.

- statistics -
**Richard**, Thursday, November 12, 2015 at 12:11am
1.50

## Answer This Question

## Related Questions

- statistics - Accuracy of price scanners at Wal-Mart. The National Institute for...
- Statistics - In the Federal Trade Commission (FTC) \Price Check" study of ...
- Statistics Help please - Is Scanner Accuracy the Same for Specials? In a study ...
- Please help with Statistics - : Is Scanner Accuracy the Same for Specials? 176 ...
- Help with statistics - In a study of store checkout scanning systems, samples of...
- Pre-Calculus - Cost,Revenue,and Profit: Estimate the number of scanners that ...
- algebra - please check and correct if needed. thanks problem: you have coupon of...
- microeconomics - The Consumer Price Index (CPI) for the year 2012 is 2.412 and ...
- Business (Linear Programming) - Wal-Mart, a discount store chain, is planning to...
- Business (Linear Programming) - Wal-Mart, a discount store chain, is planning to...

More Related Questions