Posted by Priya on Sunday, October 14, 2012 at 7:27am.
Supplier ontime delivery performance is critical to enabling the buyer’s organization to meet its customer service commitments. Therefore, monitoring supplier delivery times is critical. Based on a great deal of historical data, a manufacturer of personal computers ﬁnds for one of its justintime suppliers that the delivery times are random and well approximated by the Normal distribution with mean 48.2 minutes and standard deviation 13.4 minutes.
(a) What is the probability that a particular delivery will exceed one hour?
(b) Based on part (a), what is the probability that a particular delivery arrives in less than one hour?
(c) What is the probability that the mean time of 5 deliveries will exceed one hour?

Math  Reiny, Sunday, October 14, 2012 at 10:33am
in
http://davidmlane.com/normal.html
I entered:
mean  48.2
SD  13.4
click on "above" and enter 60 (for 1 hour) to get
.1893
etc 
Math  hi, Tuesday, March 12, 2013 at 9:43pm
78