# Read the problem carefully and answer the questions to complete this assignment.

Read the problem carefully and answer the questions to complete this assignment. Part I is based on Chapter 1& 2. Part II is based on the concepts you learned in chapter 6. Use appropriate notations whenever necessary. Use a calculator/ StatKey or other technology as needed to complete this problem. For the dot plot and boxplot, include a screenshot/ image. Submit the entire project (all parts) as a single word document on blackboard- Projects folder.
Finish part I by 10/17 (Just finish; you do not have to submit the work)
Finish part II and III by 12/12 (Submit this completed project on blackboard on or before this date)
Problem:
The “Jupiter Bar” is a candy bar that is only manufactured and sold in one size. Tens of thousands of bars are manufactured every day. Nutritional content appears on the bar’s wrapper, including a statement that a given bar has a sodium content of 96 milligrams.
Due to variability inherent in all manufacturing, we know that some bars would have slightly less than 96 milligrams of sodium and some bars would have more than 96 milligrams of sodium even if the value of “96 milligrams” appears on the wrapper. However, there is a concern that the average sodium content in all Jupiter Bars is actually more than 96 milligrams, and we have been asked to investigate.
Here are the sodium measurements (in milligrams) from a sample of 20 Jupiter Bars:
88
95
98
101
98
103
96
99
112
90
109
99
101
110
105
102
105
102
95
104
Part I (40 Points)
1) Give summary statistics for the sample data.
2) Create a dot plot of the sample data.
3) Create a box plot of the sample data.
4) In order for us to use this sample of 20 Jupiter Bars to make inferences about the whole population of Jupiter Bars, what assumption must we make regarding the sample and how it was obtained? What risk do we run in performing any inference about the population if this assumption is not met?
5) Assuming that the sampling was done properly, name two ways in which the summary statistics and graphs above suggest that the population average sodium content might be more than 96 milligrams?
Part II (50 Points)
Based on our analysis of our sample data, we are asked to perform a formal hypothesis test (test of significance) to examine if the average sodium content of all Jupiter Bars may actually be more than 96 milligrams.
6) Develop the correct null and alternative hypotheses using standard statistics symbols, using words, or using both.
7) Based on the context of the question we are investigating and the nature of our sample data:
a) Choose an appropriate test procedure and list that procedure here.
b) State any assumptions or conditions regarding your sample and/or the population that are necessary for the test procedure you have chosen.
c) Compute the correct test statistic value and record that value here to 3 decimal places (X.XXX).
(If you are using the formula: write down the formula and show all work. If you are using calculator/ other technology – state the menu, and copy down the details or include screenshot)
d) Compute the correct p-value based on both the test statistic and your hypotheses and record that p-value here to 5 decimal places (X.XXXXX)
e) Using a significance level of 3%, state clearly if you are rejecting the null hypothesis or failing to reject the null hypothesis.
Part III (10 Points)
A journalist is writing an article about the results of your investigation and has asked you for a one or two sentence quote to include in the article. The journalist asks “What was the purpose of the investigation? What did you conclude? Keep in mind that our readers probably never took a statistics course.”
In the space below, write one or two sentences that answer both of the journalist’s questions in a way that is easily understood by the general public AND is consistent with your work in Part II.
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