Question 627957
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Hi,
{{{mu}}} = 800 hours and{{{sigma}}} = 60 hours
Find the probability that a random sample of 16 bulbs will have a mean lifetime between 790 and 810 hours.
*Note: {{{z =blue (x - mu)/blue(60/sqrt(16))=blue (x - mu)/15}}}
P( z = 10/15)  - P(z = -10/15) = .7475 -.2525