SOLUTION: Find the value of z, such that P[ -z < Z < z ] = 0.5468 Last one I promise, appreciate all the help you guys have given me to prepare for my tests :)

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Question 132746: Find the value of z, such that P[ -z < Z < z ] = 0.5468
Last one I promise, appreciate all the help you guys have given me to prepare for my tests :)
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
Find the value of z, such that P[ -z < Z < z ] = 0.5468
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You need to understand this.
Draw the normal curve.
You are told the probability between -z and z is 0.5468
That interval will be centered on the mean. So there
will be an area under the curve of 0.2734 to the right
of the mean and an equal area to the left of the mean.
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If you use a z-chart look for 0.2734 in the body of the
chart; find the corresponding z-value listed on the left
side of the chart.
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If you use a TI calculator go to DISTR; select InvNorm;
enter 0.5+0.2734 or 0.5-0.2734 to get z= +0.75 or z=-0.75
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Those are the z-values you are looking for.
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If you can understand that procedure and can follow what
you are doing on your normal curve diagram you are
beginning to understand z-values.
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Cheers,
Stan H.