Question 304:

Asked on August 1, 2008

1

Answer:

No answer provided yet.

Yes. For a continuous distribution, when you calculate the z-score you subtract a data-point from the mean and divide that result by the standard deviation. For example, with a mean of 100 and standard deviation of 15, a data point of 100 has a z-score of 0 because (100-100)/15 = 0/15 = 0.

 So if the data-point is equal to the mean you would have 0 in the numerator. Zero divided by anything is zero, therefore if you know the z-score is 0, you know the unknown data-point is equal to the mean, even without knowing the standard deviation.