SOLUTION: A manufacturer knows that their items have a normally distributed lifespan, with a mean of 3.3 years, and standard deviation of 0.5 years.The 7% of items with the shortest lifespan
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Question 1147643: A manufacturer knows that their items have a normally distributed lifespan, with a mean of 3.3 years, and standard deviation of 0.5 years.The 7% of items with the shortest lifespan will last less than how many years? Answer by rothauserc(4718) (Show Source):
You can put this solution on YOUR website! The z-score associated with a probability of 0.07 is -1.47
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Note use table of z-scores to lookup probabilities
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(X - 3.3)/0.5 = -1.47
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X - 3.3 = −0.735
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X = 2.565 is approximately 3
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Therefore, we can expect 3 items have shortest lifespan represent 7% of all items
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