Hi,
z-scores tell the tAle as well. Some feel more comfortable using Percentages.
z-scores need not be converted to percentage to compare them:
done below to give more insight to the Standard Normal Curve.
Percentages given represent area under curve to the left of the z-score
Score Mean Standard Deviation Z-Score
Oral Interpret 38, 40, 10,42%
Persuasion 28, 20, 20, 0.4 65%
Theory Building 45, 30 , 20, .75 77%
Below: z = 0, z = ± 1, z= ±2 , z= ±3 are plotted.
Note: z = 0 (x value the mean) 50% of the area under the curve is to the left and %50 to the right