Assignment:
A meat processing plant has processed an average of 100 tons per day for the last several years. Newer processing machines have been installed recently. The quality control manager would like to know whether this average has improved. She randomly selects 40 days from the computer database and computes the average and standard deviation of n = 40 days to be 105 tons and 8 tons, respectively. Is this an experiment or an observational study and why?
Provide complete and step by step solution for the question and show calculations and use formulas.