#1. A random sample of 28 observations gave a correlation coefficient of 0.45. Test the hypothesis at the 0.05 level of significance that the population correlation coefficient is zero? Q2# The weights of 6 persons before they stopped smoking and 5 weeks after they stopped smoking are as follows: Person 1 2 3 4 5 6 Before After 150 145 176 174 155 151 116 110 158 155 165 158 Use the t-test for paired observations to test the hypothesis at the 0.05 level of significance, that giving up smoking has no effect on a person's weight. Q3# Mr. Ahmad is the budget director for the company. He would like to compare the daily travel expenses for the sales staff (Group S) and the audit staff (Group A). He collected the following information: Group A 131, 135, 146, 165, 136, 142 Group S 130, 102, 129, 143, 149, 120, 139 Determine whether the mean daily expenses of the two groups differ significantly at the 0.05 level of significance. The expenses are assumed to be normally distributed and the standard deviation for each group is the same. Q#4 The following sample observations were randomly selected X 5 3 6 3 4 4 6 8 Y 13 15 7 12 13 11 9 5 Determine the coefficient of correlation and interpret the result. Q5# Find and test whether the two attributes are independent. Let Attributes A1 A2 A3 Total B1 B2 215 135 325 175 60 90 600 400 Total 350 500 150 1000