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• <br />• <br />u <br />The assumption of a normal distribution of ash values is also similar to that assumption <br />with the BTU values. The theoretical number of samples within one standard deviation of the <br />mean is 20.4; the actual number of samples within one standard deviation of the mean is 26. <br />Values between 9.02 and 21.0 <br />Values > 21.0 <br />Values < 9.02 <br />Theoretical With <br />Normal Distribution Actual <br />20.4 26 <br />4.8 3 <br />4.8 3 <br />2a <br />Thus, the distribution is not exactly normal, but it approximates normality in the same way <br />that the distribution of BTU values approximates normality and skewness is not present. <br />MOISTURE <br />Moisture content of the thirty samples illustrated a large range (7.09) but a strong central <br />tendency was present with a standard deviation of 1.73 about mean of 8.60. No major <br />differences were observed between the twelve channel samples as a group and the eighteen <br />drill samples as a group. A strong negative skewness was observed. <br />VOLATILE MATERIAL <br />Only four of the channel samples were tested for volatile material; however, all eighteen <br />drill samples were tested. Therefore, any generalized observation based upon an analysis of <br />the raw data would be more tenuous than the observations presented above. Based upon <br />twenty-two samples; however, a fairly large range of 15.62 was observed. A strong central <br />tendency was also observed, as illustrated by a standard deviation of 2.31 about a mean of <br />33.27. The skewness of the distribution was insignificant. <br />MC <br />Volume 1 <br />4-29-96 <br />