K & T day care services goes through an average of 45 Pureen Dry 5 disposable diapers every 10 working days. The 95% confidence interval for the average number of diapers is 39 ≤ µ ≤ 51 disposable diapers.
Last year K & T went through an average of 40 disposable diapers every 10 working days.
1. Consider the average of 40 disposable diapers as a pre-existing known value - a pre-existing population mean. Is K & T using a statistically significantly higher average number of diapers than last year (yes or no)?
2. Based on the data provided, explain why you answered number one the way you did.
