A manufacturer knows that their items have a normally distributed lifespan, with a mean of 7 years, and standard deviation of 1.6 years.

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Question: A manufacturer knows that their items have a normally distributed lifespan, with a mean of 7 years, and standard deviation of 1.6 years.

If you randomly purchase one item, what is the probability it will last longer than 11 years?

Given: a manufacturer knows that their items have a normally distributed lifespan with mean =  7 years and a standard deviation = 1.6 years.

That is:  X follows Normal distribution ( \mu = 7 , \: \: \sigma = 1.6 )