Hypothesis testing for difference between two mean suppose equal variances.
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1

3.481

3.448

3.485

3.475

3.472


3.477

3.472

3.464

3.472

3.470


3.470

3.470

3.477

3.473

3.474

2

3.258

3.254

3.256

3.249

3.241


3.254

3.247

3.257

3.239

3.250


3.258

3.239

3.245

3.240

3.254

An article measured the capability of a gauge by measuring the weights of 2 sheets of paper. The data is in the table.
a) Make sure the assumption that the data from each sheet are from normal dist.
b) Test the hypothesis that the mean weight of the 2 sheets are equal against the alternative that they are not (assume equal variances). Use α=0.05 and assume equal variances. Find the P value.
c) Repeat the previous test with α=0.10
d) Evaluate the answers from parts b and c an describe why they are the same or why are they different.
e) Describe how problems in parts b and c could be answered with confidence intervals.