Question

Many cardiac patients wear an implanted pacemaker to control their heartbeat. A plastic connector module mounts on the top of the pacemaker. Assuming a standard deviation of 0.002 inch and an approximately normal distribution, how large a sample is needed if we wish to be 95% confident that our sample mean will be within 0.0005 inch of the true mean?

Answer 1

It is given that . The sample mean will be within 0.0005 inch of the true mean implies that the margin of error should be .

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First let us consider teh eqiality

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