Question 334:

Asked on August 10, 2008

Tags: Z-Score

1

Answer:

No answer provided yet.

You're looking for the z-value for 80% of the area under the curve. Use the percentile to z-score calculator and select 1-sided area for .80. You should get a z-score of 0.8419.

You can visualize this by looking at the interactive graph of the standard normal curve (see the second graph for 1-sided area). Hover over the curve until it shows "white-area" to be 20% and you should se approx a z-score of .84.