SOLUTION: A local medical research association proposes to sponsor a footrace. The average time it takes to run the course is 45.8 minutes with a standard deviation of 36 minutes. If the ass

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Question 195262: A local medical research association proposes to sponsor a footrace. The average time it takes to run the course is 45.8 minutes with a standard deviation of 36 minutes. If the association decides to include only the top 25% of the racers, what should be the cut off time in the tryout run? Assume the variable is normally distributed. Would a person who runs the course in 40 minutes qualify?
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
A local medical research association proposes to sponsor a footrace. The average time it takes to run the course is 45.8 minutes with a standard deviation of 36 minutes. If the association decides to include only the top 25% of the racers, what should be the cut off time in the tryout run? Assume the variable is normally distributed. Would a person who runs the course in 40 minutes qualify?
67
Find the z-value associated with the top 25% point.
InVNorm(0.75) = 0.6745
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Find the corresponding raw score value.
x = zs + u
x = 0.6745*36 + 45.8
x = 70.08 minutes (cut-off time)
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40 minutes? Sure
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Cheers,
Stan H.