Question 1158879
you have p(z < c) = .8389
that represents the area to the left of the z-score.
using the online z-score calculator that can be found at <a href = "" target = "_blank"></a>, the z-score is equal to .99.
this is what it looks like on that calculator.


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you are using the value from an area portion of the calculator and looking for the area to the left of the z-score.
the area to the left of the z-score is the area that is below the z-score.