Posted by Jennifer on Thursday, October 13, 2011 at 9:28am.
A set of 50 data values has a mean of 15 and a variance of 25. Find the standard score of a data value = 20

statistics  drwls, Thursday, October 13, 2011 at 10:29am
The "standard score" is more commonly called the "zscore".
It is the number of "standard deviations" above the mean.
The standard deviation is the square root of the variance, or 5 in this case.
The number of data values is not needed to answer the question.
A data point of 20 is one standard deviation above the mean of 15, so the standard or "z" score is 1.0 
Can someone help me please?  Jennifer, Thursday, October 13, 2011 at 12:32pm
Statistics confuses me....thank you for your help :)

Can someone help me please?  Anonymous, Friday, July 13, 2012 at 7:52pm
A zscore is 0.6 standard deviations above the mean.