b) Solve with the assumption that neither of the population mean nor the population standard deviation is known.
 

4. The following scores represent the final examination grades for an elementary statistics course: 23 60 79 57 74 52 70 82 36 80 77 95 41 65 92 85 55 76 52 64 75 78 25 80 98 81 67 71 83 54 64 72 88 62 74 60 78 89 76 84 48 84 90 79 34 67 17 82 69 74 63 85 61 Test the goodness of fit between the observed class frequencies and the corresponding expected frequencies of a normal distribution with = 64 and o = 21, using a 0.05 level of significance. 32 1 10 1 43 15 80 81 41