Reference no: EM132844696

The Phillies were accused of cheating their beer customers by not putting enough beer in their 12 oz cups. When 15 cups were selected at random, they were found to have a mean of 11.7 ounces with a standard deviation of 0.5 ounces. At the .01 significance level, test the claim that the customers are being cheated.

An employer claims that full time employees have a mean income of $35,000. A sample of 200 employees was considered. Their mean salary was $34,000. Assume a population standard deviation of $4,000. Does her claim seem reasonable at a 0.05 level of significance?

You want to estimate the percentage of statistics students who get grades of C or better. How many students should you survey to be 95% confident that the sample percentage is off by no more than 2 percentage points.

A researcher wants to estimate the mean serum cholesterol level for college age women. In a past study the standard deviation for this measure was 42 units. If the researcher wants to be off in his estimate by no more than three units (with 99% confidence), how large must his sample be?