Question

Find the Z-scores for which 80% of the distribution's area lies between - z and Z.Click to view page 1 of the table. Click to view page 2 of the table.The Z-scores are (Use a comma to separate answers as needed. Round to two decimal places as needed.

Answer 1

• We know that the area of the distribution has to add up to 100% because that isour probability.

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• So, 80 % (or 0.8) of the Z score is between two z-scores ,

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• From left it will be 10% or 0.1 and from the right it wil also be 10% or 0.1. { 0.1+0.8+0.1 =1}

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• The normal distrbution table gives a Z -score of -1.28 and 1.28 for a 80%(0.8) distribution area.