The given data; 10,30,20 The mean will be (10+30+20)/3 = 20 Deviation from the mean will be; -10, 10, 0 Square of the deviations will be; 100, 100, 0 The sum of the square of the deviations = 200 The variance will therefore be; sum of the square of deviations from the mean divided by the N (3) = 200/3 = 66.67 Thus; the variance = 66.67
2x2 for each pen with four in a square and one to the side kind of like this
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each length of fencing would be 2 meters and the total square footage would be 20 meters because some of the fencing is used for more than one pig's pen
the dimensions would be hard to show, but 4x4+ a 2x2
