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.

a) Find a 96% confidence interval for the mean of the depths of all connector modules made by a certain manufacturing company. A random sample of 25 modules has an average depth of 0.310 inch.

b) How large a sample is needed if we wish to be 96% confident that our sample mean will be within 0.0005 inch of the true mean?

Answer 1