Question

A soft drinks distributor claims that a new advertising display will increase sales by average of 50 cases per week.For a random sample of 25 stores, the average sales increase was 41.3 cases and the sample standard deviation was 12.2 cases. Test at the 5% level the null hypothesis that population mean sales increase is at least 50 cases.

• A. The test statistic is -1.645; The critical value is -3.57; we reject Ho and accept the alternative.
• B. The test statistic is -3.57; The critical value is -1.645; we reject Ho and accept the alternative.
• C. The test statistic is -3.57; The critical value is -1.711; we reject Ho and accept the alternative.
• D. The test statistic is -3.57; The critical value is 1.711; we fail to reject Ho.

Answer 1