SOLUTION: Need instructions of how they get the answer... A doctor believes that the standard deviation of systolic blood pressure is 450. A random sample of 24 patients found a standard

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Question 320860: Need instructions of how they get the answer...
A doctor believes that the standard deviation of systolic blood pressure is 450. A random sample of 24 patients found a standard deviation of 520. Assume the variable is normally distributed and a=0.01. What are the critical value?

What formula / steps should be used on this...since there are two standard deviaitons...
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
A doctor believes that the standard deviation of systolic blood pressure is 450.
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A random sample of 24 patients found a standard deviation of 520.
Assume the variable is normally distributed and a=0.01.
What is the critical value?
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The problem statement implies you will do an F-test.
You need to look at an F-distribution Table and find
the F value with a right tail of 1% with the proper
degrees of freedom.
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F= larger variance/smaller variance = 520/450
df for numerator: 23
df for denominator: infinity
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Ans: F-value for right-tail of 1% = 1.6402
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Cheers,
Stan H.