MTH 380 Lecture Notes - Lecture 8: Vtt Technical Research Centre Of Finland
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(1lA random sample bf n = l-5 observations was selected from a normal population. The sample mean and
variance were x :3.91 and s2 =0.32l4.Find a90% confidence intervalforthe population varianceo2.
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Finda90%confidenceintervalforpopulationvariance.Assumethatasampleof obtainedmeasurements ssee.:el
from normal population of all possible measure that can be obtained for the given object.
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Af precision instrument is guaranteed to read accurateiy to within 2 units. A sample of four instrun ent :ea: -:s c-
the same object yielded the measurements 353, 351, 351, and 355.
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