The life expectancy of a typical lightbulb is normally distributed with a mean of 3,000 hours and a standard deviation of 38 hours. What is the probability that a lightbulb will last between 2,975 and 3,050 hours?

Question

solomonzelman · Answer

You are posting one question before you finish with the previous one.

solomonzelman · Answer

Don't post new question before finishing the previous question. You needed to find aver. rate of change, didn't you ?

ganeshie8 · Answer

tough question, 
do u knw how to calculate zscore and grab areas from zscore table ?

anonymous · Answer

0.5565

 0.6520

 0.3545

 0.6250

anonymous · Answer

i dont have the z table on me right now

ganeshie8 · Answer

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