SOLUTION: Assuming that the weights of newborn babies are normally distributed with mean 6.5 lbs and standard deviation 1.2lbs, how many babies in a group of 80 do we expect to weight more t

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Question 855430: Assuming that the weights of newborn babies are normally distributed with mean 6.5 lbs and standard deviation 1.2lbs, how many babies in a group of 80 do we expect to weight more than 8.9lbs?
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
m = 6.5
s = 1.21
z = (x-m)/s
x = 8.9
z = (8.9-6.5)/1.21 = 2.4/1.21 = 1.98
p(z < 1.98) = .9761 from the following z-score table
http://lilt.ilstu.edu/dasacke/eco148/ztable.htm
p(z > 1.98) = 1 - .9761 = .0239
out of 80 babies, .0239 * 80 = 1.912 are expected to be over 8.9 pounds.