Statisitics:Standard Deviation of Population and o
posted by Carma .
Standard Deviation of Population and of a Sample
The weight of newborn children in the United States vary according to the normal
distribution with mean 7.7 pounds and standard deviation 1.68 pounds. The government
classifies a newborn as having low birth weight if the weight is less than 5.7 pounds.
a) What is the probability that a baby chosen at random weighs less than 5.7 pounds at
birth?
b) You choose three babies at random. What is the probability that their average birth
weight is less tan 5.7 pounds?

The weight x of all female German Shepherds is approximately normally distributed with population mean u=64 pounds and population standard deviation of o=8 pounds. a)What is the probability that a randomly selected female german shepherd weighs more than 75 pounds? p(x>75)?)