Mathematics and Mathematical Literacy - Thutong

Mathematics(NSC)/Grade 12/ P2 42 Exemplar6.2 The test results and variouscalculations for 20 students appearin the table alongside.Test results ( x x)−2( x − x)59 -3,7 13,6958 -4,7 22,0957 -5,7 32,4955 -7,7 59,2968 5,3 28,0954 -8,7 75,6989 26,3 691,6973 10,3 106,0960 -2,7 7,2998 35,3 1246,0965 2,3 5,2918 -44,7 1998,0959 -3,7 13,6948 -14,7 216,0958 -4,7 22,0956 -6,7 44,8972 9,3 86,4960 -2,7 7,2974 11,3 127,6973 10,3 106,09x = 62,7∑2( x− x) = 4910,26.2.1 Determine the standard deviation of the test results (2)6.2.2 Determine what percent of the students scored within one standarddeviation of the mean. (3)6.2.3 Hence, or otherwise, determine whether the test results approximate anormal distribution. Justify your answer. (3)[17]Copyright reserved