Lesson 4

Lesson 4 Summary

Z-scores can be used to solve problems when you are dealing with normally distributed data values that are not exactly one, two, or three standard deviations away from the mean. Z-scores and the standard normal distribution can also be used to compare different sets of normally distributed data.

Different strategies can be used to determine the percent of data that is less than or greater than a given value in a normal distribution. Whether you use a z-score table or a graphing calculator, it is important to always keep in mind what area under the curve you are dealing with. Ask yourself this: does the situation refer to the area under the curve to the left or the right of the data value or z-score?

In Lesson 5 you will continue to solve problems using z-scores.