SOLUTION: Let the random variable Z follow a standard normal distribution. The probability is 0.25 that Z is less than what number?

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Question 601855: Let the random variable Z follow a standard normal distribution. The probability is 0.25 that Z is less than what number?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Let the random variable Z follow a standard normal distribution. The probability is 0.25 that Z is less than what number?
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Draw a normal curve
Let the horizontal base be the z line.
z = 0 is the middle point of that base.
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Find a point that has 0.25 of the area to the left.
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Find the z-value of that point.
inv(0.25) = -0.6745
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Note: P(z < -0.6745) = 0.25
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Cheers,
Stan H.