SOLUTION: The length of human pregnancies from conception to birth varies according to a distribution that is approximately Normal with mean 266 days and standard deviation 16 days. What is

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Question 1050168: The length of human pregnancies from conception to birth varies according to a distribution that is approximately Normal with mean 266 days and standard deviation 16 days. What is the probability that the average pregnancy length for six randomly chosen women exceeds 270 days?
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
z+=blue+%28x+-+mu%29%2Fblue%28sigma%2Fsqrt%28n%29%29
P(x>270) = 1 - P(<=270) = 1- P(z<= (270-266)/(16/sqrt(6)) = 1- P(z<= .6124)
P(z<= .6124) = .73
P(x>270) = 1- P(z<= .6124) = 1 -.73 = .27