SOLUTION: The hours a college freshman spend studying each week is usually distributed with a mean of 8 hours and a standard deviation of 5.5 hours. Determine the % of students who spend bet

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Question 1041608: The hours a college freshman spend studying each week is usually distributed with a mean of 8 hours and a standard deviation of 5.5 hours. Determine the % of students who spend between 2.5 and 19 hours studying each week?
A.) 34%
B.) 68%
C.) 47.5%
D.) 81.5%
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
The hours a college freshman spend studying each week is usually distributed with a mean of 8 hours and a standard deviation of 5.5 hours. Determine the % of students who spend between 2.5 and 19 hours studying each week?
Find the z-value of 2.5 and the z-value of 19
Find the probability that z lies between those values.
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z(2.5) = (2.5-8)/5.5 = -1
z(19) = (19-8)/5.5 = 2
P(2.5 < x < 5.5) = P(-1 < z < 2) = 0.819 = 81.9%
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A.) 34%
B.) 68%
C.) 47.5%
D.) 81.5%
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Cheers,
Stan H.
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