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For example, suppose it is desired to determine the number of <br />samples for corrugated paper to within 2 percentage units ( _ <br />0.02) and corrugated paper composes 10% (X = 0.10) of the waste <br />stream. First, the percentage of paper is analyzed to see whether <br />or not it is greater or less than 0.5. If the percentage of paper <br />in decimal form is less than 0.5 then the precision unit ( ) is <br />additive; if not then the precision unit is subtracted. Next, the <br />values for X and X + are transformed using Table 5 and inserted <br />into the equation for sensitivity. Finally, having all the <br />variables computed the number of samples can be determined using <br />equation 1 stated earlier. <br />RESULTS AND ANALYSIS : <br />The number of samples for composition analysis of refuse was <br />determined using the waste characterization study for the County of <br />San Joaquin. It was found that the optimal number of samples <br />needed for an accurate estimate of each waste component to be <br />between approximately 40 and 12 using one and two percentage units <br />respectively. It was in the interest of this paper to recommend <br />that 30 samples be of sufficient size for determining the true <br />percentage of all components in the waste stream. This size will <br />require less time, labor, and money while maintaining a good degree <br />of accuracy. <br />If it is desired to improve the accuracy of the study then a <br />smaller precision can be chosen. However, by choosing a smaller <br />precision it is inevitable that the number of samples will increase <br />in order to accommodate a more accurate study. For this reason <br />calculations for determining the number of samples were performed <br />using two different precision units. <br />11 <br />r <br />Attachment A 3 <br />U <br />11 <br />