A battery manufacturer has just begun distribution of its SuperVolt, a 6-volt lantern battery for outdoor enthusiasts. Prototype tests of the new battery found the average lifetime in continuous use to be 8 hours, with a standard deviation of 2 hours. Battery lifetimes in such applications have been approximately normally distributed. Edgar Evans, the consumer reporter for a large metropolitan newspaper, has purchased one of the batteries to take along on a camping trip. On the first day of his trip, Edgar goes fishing in his rowboat, becomes disoriented, and gets lost among the many small islands in the large lake near his camp. Fortunately, Edgar has brought along his trusty flashlight and its new SuperVolt battery. At 9 p.m., Edgar turns on his flashlight and shines it into the air, hoping that someone will see his signal and rescue him. Unfortunately, it is not until 3 a.m. that searchers begin their flight over the lake. If Edgar’s light is still shining as they become airborne, they will easily spot it from the air. When Edgar finally gets back to the city, what is the probability that he will have an exciting story to tell about how his flashlight and its SuperVolt battery were two of the heroes in his rescue?

  • CreatedSeptember 08, 2015
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