A major television manufacturer has determined that its 40-inch LED televisions have a mean service life that can be modeled by a normal distribution with a mean of six years and a standard deviation of one- half year.
a. What probability can you assign to service lives of at least?
(1) Five years?
(2) Six years?
(3) Seven and one- half years?
b. If the manufacturer offers service contracts of four years on these televisions what percentage can be expected to fail from wear- out during the service period?