A packaging company would like to reduce the variability in the amount of coffee that is packaged. so it is evaluating a new packaging machine. They take a sample of 46 bags from their current machine and find a mean weight of 12.1 ounce and standard deviation of 3.6 ounce. They then collect a sample of 63 bags from the new machine and find a mean weight of 12.2 ounce and standard deviation of 2.7 ounce. Perform the appropriate test to determine if the new machine has a lower variance than the old one. Use alpha=0.05
Added by Shelby S.
Step 1
Null hypothesis (H0): The variances of the two machines are equal, i.e., σ1^2 = σ2^2. Alternative hypothesis (H1): The variance of the new machine is less than the old one, i.e., σ1^2 > σ2^2. Show more…
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