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What is the seventh decile of the following data points?> >>>
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81> > |
84> > |
91> > |
97 |
102 |
108 |
110 |
112 |
115 |
121 |
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128 |
135 |
138 |
141 |
142 |
147 |
153 |
155 |
159 |
162 |
Your answer: C was incorrect. The correct answer was A) 141.7.
The formula for determining quantiles is: Ly = (n + 1)(y) / (100). (could you please explain this fomula?)Here, we are looking for the seventh decile (70 percent of the observations lie below) and the formula is: (21)(70)/(100) = 14.7. The seventh decile falls between 141.0 and 142.0, the fourteenth and fifteenth numbers from the left. Since L is not a whole number, we interpolate as: 141.0 + (0.70)(142.0 − 141.0) = 141.7. | 
发表于 2006-4-17 21:45
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