P-value when sample SDEV differs from population

If a sample or sub-population has the same mean as, but a different standard deviation from, the general population, how do I test whether this difference is significant?

For example: I purchased a hamburger machine from a line of machines known to produce 100g beef patties with a standard deviation of 5g. The average weight of my first 100 patties was not significantly different from 100g, but the standard deviation of the batch was 9g. Can I conclude my machine is defective, and if so, what is the p-value of my conclusion?

Use a chi-square test.


Well that was easy :slight_smile: