In a z-score calculation, if z equals zero, what does the corresponding value equal?

• A. The mean
• B. The maximum
• C. The minimum
• D. The standard deviation

Answer: (A)

Z-scores tell you how far a value is from the mean in units of standard deviation. The formula is z = (X − μ) / σ. If the z-score is zero, the difference X − μ must be zero, so X equals the mean. This means the value sits exactly at the center of the distribution. The standard deviation is the scaling factor used to convert deviations into z-scores, not the value itself when z is zero. Maximum and minimum are related to large positive or negative z-scores, not zero.