STAT421 HW 6 1. Let the quantity of the production of a new machine and of the old machine are two population and normally distributed. Find the confidence interval estimation of the differences...

Extracted text: STAT421 HW 6 1. Let the quantity of the production of a new machine and of the old machine are two population and normally distributed. Find the confidence interval estimation of the differences between the means of the two populations. X1 X2 42.1 42.7 41 43.6 41.3 43.8 41.8 43.3 42.4 42.5 42.8 43.5 43.2 43.1 42.3 41.7 41.8 44 42.7 44.1 Where X1: New machine and X2: Old machine.