A.
Since about 95% of a normal distribution falls within two standard deviations of the mean, that leaves 5% that lie without, with 2.5% lying to either side.
b.
About 68% of a normal distribution lies within one standard deviation of the mean, so this probability is about 0.68.
c. You're looking for
such that
Since
occurs for
, it follows that
So there's a probability of 0.10 for having a demand exceeding about 1328 pounds.
Since about 95% of a normal distribution falls within two standard deviations of the mean, that leaves 5% that lie without, with 2.5% lying to either side.
b.
About 68% of a normal distribution lies within one standard deviation of the mean, so this probability is about 0.68.
c. You're looking for
Since
occurs for
So there's a probability of 0.10 for having a demand exceeding about 1328 pounds.