s3 estimation - arghhhhhhhh
Maths and statistics discussion, revision, exam and homework help.
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s3 estimation - arghhhhhhhhi am stumped!
an electrical company repairs very large numbers of television sets and wishes to estimate the mean time taken to repair a particular fault. it is known from previous research that the standard deviation of the time taken to repair this fault is 2.5 minutes. the manager wishes to ensure that the probability that the estimate differs from the true mean by less than 30 seconds is 0.95. find how large a sample is required.
i reckon that p(|e - μ | < 0) < 0.95 where e is the estimate
is that correct? and what on earth do i do next? thanks so much for the help, i'm self-teaching and feeling very discouraged! -
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Re: s3 estimation - arghhhhhhhhI got P(|μ-x̄|<30)=0.95, where μ is the true mean and x̄ is the estimated mean. To calculate this you will need x̄ - was there a previous part to this question?(Original post by manyriverstocross)
i reckon that p(|e - μ | < 0) < 0.95 where e is the estimate
