Find the mean of the following data. (a) 9, 7, 11, 13, 2, 4, 5, 5 (b) 16, 18, 19, 21, 23, 23, 27, 29, 29, 35 (c) 2.2, 10.2, 14.7, 5.9, 4.9, 11.1, 10.5 (d) 11/4, 21/2, 51/2, 31/4, 21/2
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