Find the raw score (X) for z-score = 2.50

Expert Answers
sciencesolve eNotes educator| Certified Educator

You need to use the equation that relates the raw score and the z score such that:

`z = (x - mu)/sigma`

x represents the raw score, `sigma`  represents the standard deviation and `mu`  is the mean.

Notice that the problem gives only the value of z score, hence, you should substitute this value in the equation above such that:

`2.5 = (x - mu)/sigma =gt 2.5 sigma = x - mu`

You need to isolate the raw score such that:

`x = mu + 2.5 sigma`

Hence, evaluating the raw score if only the z score is given yields `x = mu + 2.5 sigma`  .