Replacement times for T.V. sets are normally distributed with a mean of 8.2 years and a standard ...

Replacement times for T.V. sets are normally distributed with a mean of 8.2 years and a standard deviation of 1.1 years (based on data from Getting Things Fixed, Consumers Reports). (a) Find the probability that a randomly selected T.V.
 
  will have a replacement time between 6.5 and 9.5 years. (b) Find the probability that a randomly selected T.V. will have a replacement time between 9.5 and 10.5 years. These two problems are solved almost exactly the same. Draw the diagram for each and discuss the part of the solution that would be different in finding the requested probabilities.