Posted by Rhea on Sunday, September 26, 2010 at 12:42am.
A statistics practitioner determined that the mean and standard deviation of a data set were 120and 30, respectively. What can you say about the proportions of observations that lie between each of the following intervals?
a. 90 and 150
b. 60 and 180
c. 30 and 210

Statistics  PsyDAG, Sunday, September 26, 2010 at 11:28am
Z = (scoremean)/SD
Calculate the respective Z scores. Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportions related to these Z scores. 
Statistics  adasdsad, Monday, March 13, 2017 at 8:37pm
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