Lesson 6.3: z-Scores

In the previous lesson you learned that you can predict the likelihood of certain events when data is normally distributed. You did this by finding the area under the normal curve for certain ranges of data values. However, the only areas you worked with were based on measurements that were a whole number of standard deviations from the mean. In real-life problems, the need to answer questions about data values that don't correspond to whole number increments of the standard deviation is very common. In this lesson you will learn how to find the area under a normal curve corresponding to any data value(s).


In Lesson 6.3, you will

  • determine z-scores for data values
  • use z-scores to determine the area under a normal curve
  • solve problems using areas under a normal curve