Consider the accompanying data on breaking load (kg/25mm width) for various fabrics in both an unabraded condition and abraded condition. ("The effect of wet abrasive wear on the tensile properties of cotton and polyester-cotton fabrics," J.Testing and Evaluation, 1993: 84-93). Use the paired t-test, as did the authors of the cited article to test null hypothesis and alternative hypothesis at significance level 0.01. (See attached file for full problem description and data table)
This solution finds the mean, standard deviation and variance to determine the test statistic for the t-test. Finally, a decision is made to accept or reject the null hypothesis.