SOLUTION: A random variable x has a mean of 100 and a standard deviation of 10 Find P (85≤ x ≤ 115 )

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Question 933331: A random variable x has a mean of 100 and a standard deviation of 10 Find P (85≤ x ≤ 115 )

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A random variable x has a mean of 100 and a standard deviation of 10 Find P (85≤ x ≤ 115 )
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z(85) = (85-100)/10 = -15/10 = -3/2
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z(115) = (115-100)/10 = 15/10 = 3/2
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P(85<= x <=115) = P(-3/2 <= z <= 3/2) = normalcdf(-1.5,1.5) = 0.8664
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Cheers,
Stan H.
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