SOLUTION: How do I solve this problem? Suppose that the time required to complete a 1040R tax form is normally distributed with a mean of 90 minutes and a standard deviation of 20 minutes

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Question 358361: How do I solve this problem?
Suppose that the time required to complete a 1040R tax form is normally distributed with a mean of 90 minutes and a standard deviation of 20 minutes. What proportion of 1040R tax forms will be completed in at least 119 minutes: Round your answer to at least four decimal places.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Suppose that the time required to complete a 1040R tax form is normally distributed with a mean of 90 minutes and a standard deviation of 20 minutes. What proportion of 1040R tax forms will be completed in at least 119 minutes: Round your answer to at least four decimal places.
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z(119) = (119-90)/20 = 1.45
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P(x>= 119) = P(z>= 1.45) = normalcdf(1.45,100,) = 0.0735
Proportion: 7.35/100
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Cheers,
Stan H.