How do you find the z-score for which 76% of the distribution's area lies between -z and z?

1 Answer
May 18, 2015

Firstly in this question, we need to solve for alpha which is the part of the distribution of which we not looking for.

we can do this with the sum:
alpha = 1 - 0.76 = 0.24

as 0.76 = 76%

we also know that our Standard Normal Distribution is symmetric, so we must divide that alpha to be split on either side of our distribution. so we solve for:

alpha/2 = 0.24/2 = 0.12

then we find a correlating z-score for the value 0.12

and we get that -z = -1.175 and z = 1.175

This becomes easier to understand when visualized, so observe how we do this sum.

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