the complete question is Pulse rates of women are normally distributed with a mean of 77.5 beats per minute and a standard deviation of 11.6 beats per minute. The original pulse rates are measure with units of "beats per minute". What are the units of the corresponding z scores? Choose the correct choice below.
A. The z scores are measured with units of "beats per minute."
B. The z scores are measured with units of "minutes per beat."
C. The z scores are measured with units of "beats."
D. The z scores are numbers without units of measurement.
we know that
A z-score is the number of standard deviations from the mean a data point is. But more technically it’s a measure of how many standard deviations below or above the population mean a raw score is
The z scores are numbers without units of measurement
therefore
the answer is the option D