SOLUTION: x has normal distribution with a mean of 80.0 and a standard deviation of 3.5. Find the following: A)P(x<75.0) B) P(78.0<x<83.0) C) P(x>85.0)

Algebra ->  Probability-and-statistics -> SOLUTION: x has normal distribution with a mean of 80.0 and a standard deviation of 3.5. Find the following: A)P(x<75.0) B) P(78.0<x<83.0) C) P(x>85.0)      Log On


   

Question 615243: x has normal distribution with a mean of 80.0 and a standard deviation of 3.5. Find the following:
A)P(x<75.0)
B) P(78.0 C) P(x>85.0)
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
x has normal distribution with a mean of 80.0 and a standard deviation of 3.5. Find the following:
A)P(x<75.0)
z(75) = (75-80)/3.5 = -5/3.5 = -1.4286
P(x < 75) = P(z < -1.4286) == normalcdf(-100,-1.4386) = 0.0766
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B) P(78.0
Incomplete question.
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C) P(x>85.0)
z(85) = (85-80)/3.5 = 5/3.5 = +1.4386
P(x> 85) = 0.0766
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Cheers,
Stan H.
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