In an experiment to determine whether there is a systematic difference between the weights obtained with two different scales, 10 rock specimens were weighed, in grams, on each scale. The following data were obtained:

Can you conclude that the mean weight differs between the scales?

a. State the null and alternate hypotheses.

b. Compute the test statistic.

c. State a conclusion. Use the α = 0.01 level of significance.

Specimen Weight on Scale 1 Weight on Scale 2 1 11.23 11.27 2 14.36 14.41 3 8.33 8.35 4 10.50 10.52 5 23.42 23.41 6 9.15 9.17 7 13.47 13.52 8 6.47 6.46 9 12.40 12.45 10 19.38 19.35