Problem

A fast food restaurant executive wishes to know how many fast food meals adults eat each week. They want to construct a $99 \%$ confidence interval with an error of no more than 0.06 . A consultant has informed them that a previous study found the mean to be 7.5 fast food meals per week and found the standard deviation to be 1.4. What is the minimum sample size required to create the specified confidence interval? Round your answer up to the next integer.

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The minimum sample size required to create the specified confidence interval is \(\boxed{3613}\).

Steps

Step 1 :Given values are the mean of 7.5, standard deviation of 1.4, margin of error of 0.06, and z-score of 2.576.

Step 2 :We need to find the minimum sample size required to create the specified confidence interval.

Step 3 :The formula to calculate the sample size is \((z \cdot \sigma / E)^2\), where \(z\) is the z-score, \(\sigma\) is the standard deviation, and \(E\) is the margin of error.

Step 4 :Substitute the given values into the formula: \((2.576 \cdot 1.4 / 0.06)^2\).

Step 5 :Calculate the value to get the sample size, and round up to the next integer.

Step 6 :The minimum sample size required to create the specified confidence interval is \(\boxed{3613}\).

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