The normal curve is completely symmetric with respect to its mean. The values along the horizontal axis are known as Z values or z-scores. Relating other normal curves to the standard normal curve. As with all web pages, this applet page may disappear at any time. Given data values find the area under the normal curve between those data values.
X denotes a distribution of data values.
Z denotes the standard normal distribution. This example will show how to use z-scores and your Standard Normal Probability Table in your text to calculate areas for any normal curve. Suppose a Liberal Arts mathematics class did very well on the first test. The class average was 79.7 and the standard deviation was 10.4. The instructor decided to curve the grades.