SOLUTION: Suppose the life of a certain brand of vacuum cleaner is normally distributed with a mean life of 12 years and a standard deviation of 4 years. A vacuum cleaner is randomly chosen.

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Question 380339: Suppose the life of a certain brand of vacuum cleaner is normally distributed with a mean life of 12 years and a standard deviation of 4 years. A vacuum cleaner is randomly chosen. Find the probability that it will last more than 16 years.
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

*Note: z+=+blue%28x+-+mu%29%2Fblue%28sigma%29

  z = (16-12)/4 = 1

P(z = 1 ) = NORMSDIST(1) = .8413 

 P(lasting more than 16 yrs) = 1 - .8413 = .1587  Or 15.87 %