SOLUTION: How to solve for the critical value za/2 that corresponds to a confidence level of 80%

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Question 1072943: How to solve for the critical value za/2 that corresponds to a confidence level of 80%
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Using symmetry, the remaining area would be 20% or 0.2.
That area is split by the right and left tail so find the z value(z%5Bc%5D) that corresponds to 0.1.
So then,
P%28-z%5Bc%5D%3Cz%3Cz%5Bc%5D%29=0.8