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Performaning the Z Test for Population Mean

In fiscal 1996, the U.S. Agency for International Development provided 238,300 metric tons of corn soy blend (CSB) for development programs and emergency relief in countries throughout the world. CSB is a highly nutritious, low-cost fortified food that is partially cooked and can be incorporated into different food preparations by the recipients.

The specifications for the CSB state that the mixture should contain 2 pounds of vitamin premix for every 200 pounds of product. These specifications are designed to produce a mean vitamin C content in the final product of 40mg per 100g. A sample of 8 readings from a production run has a mean of 22.50mg per 100g with a standard deviation of 7.19mg per gram.

Is there significant evidence that this production run does not meet the specifications? Use a 1% level of significance.

1. State the Null Hypothesis and the Alternative Hypothesis
2. Determine the test statistic.
3. Determine the P-value
4. Make a decision regarding the hypotheses based on the P-value and the Level of Significance.

Solution Summary

The solution details the step by step method for computing Z test statistic for comparing population mean with an excel spreadsheet of calculations to aid understanding.