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The nutrition label for Oriental Spice Sauce states that one package of sauce has 1140milligrams of sodium. To determine if the label is accurate, the FDA randomly selects 80 packages of Oriental Spice Sauce and determines the sodium content. The sample has an average of 1089.64 milligrams of sodium per package with a sample standard deviation of 248.67 milligrams.

Calculate a 99% confidence interval for the mean sodium content in Oriental Spice Sauce.

User Cdm
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Final answer:

The 99% confidence interval for the mean sodium content in Oriental Spice Sauce is calculated to be between 1016.22 mg and 1163.06 mg per package.

Step-by-step explanation:

To calculate a 99% confidence interval for the mean sodium content in Oriental Spice Sauce, we will use the following information: the sample mean (Öx) is 1089.64 milligrams, the sample standard deviation (s) is 248.67 milligrams, and the sample size (n) is 80. We use the t-distribution because the population standard deviation is unknown.

First, we find the t-value that corresponds to a 99% confidence level and a sample size of 80, which gives us degrees of freedom (df) equal to 79. Using a t-distribution table or software, we find the t-value for a two-tailed test at the 99% confidence level and df=79 is approximately 2.64.

Next, we calculate the standard error of the mean (SEM) using the sample standard deviation divided by the square root of the sample size:

SEM = s / √n
SEM = 248.67 / √80
SEM = 27.81

Now, we can calculate the margin of error (ME) using the t-value and SEM:

ME = t-value × SEM
ME = 2.64 × 27.81
ME = 73.42

Finally, the 99% confidence interval is calculated by subtracting and adding the margin of error from the sample mean:

Lower limit = Öx - ME

= 1089.64 - 73.42

= 1016.22 mg
Upper limit = Öx + ME

= 1089.64 + 73.42

= 1163.06 mg

The 99% confidence interval for the mean sodium content per package of Oriental Spice Sauce is 1016.22 mg to 1163.06 mg.

User Yedetta
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