This full solution covers the following key subjects: data, Observations, respectively, sample, means. This expansive textbook survival guide covers 59 chapters, and 1476 solutions. Since the solution to 12E from 7.2 chapter was answered, more than 255 students have viewed the full step-by-step answer. The full step-by-step solution to problem: 12E from chapter: 7.2 was answered by , our top Statistics solution expert on 07/05/17, 04:50AM. Probability and Statistical Inference was written by and is associated to the ISBN: 9780321923271. This textbook survival guide was created for the textbook: Probability and Statistical Inference , edition: 9. The answer to “Let X and Y equal the hardness of the hot and cold water, respectively, in a campus building. Hardness is measured in terms of the calcium ion concentration (in ppm). The following data were collected (n = 12 observations of X and m = 10 observations of Y): (a) Calculate the sample means and the sample variances of these data.(b) Construct a 95% confidence interval for ?X ? ?Y, assuming that the distributions of X and Y are N(?X, ?2 X) and N(?Y, ?2 Y ), respectively.(c) Construct box plots of the two sets of data on the same graph.(d) Do the means seem to be equal or different?” is broken down into a number of easy to follow steps, and 109 words.