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## Main Question or Discussion Point

Not sure if this is the right place to post homework questions or not, but my math problem is this: A consumer magazine has contacted a simple random sample of 33 owners of a certain model of automobile and asked each owner how many defects had to be corrected within the first 2 months of ownership. The average number of defects was sample mean= 3.7, with a standard deviation of 1.8 defects. a. Use the t distribution to construct a 95% confidence interval for population mean =the average number of defects for the model and b. use the z distribution to construct a 95% confidence interval for population mean = the average number of defects for this model. c. given that the population standard deviation is not known, which of these two confidence intervals should be used as the interval estimate for the population mean?

So as far as I can figure I need to find the population mean first and then go back through and then do the Population standard deviation, to work out the first two parts of the problem. Unless there is another way of going about it, I'm not exactly sure though.

So as far as I can figure I need to find the population mean first and then go back through and then do the Population standard deviation, to work out the first two parts of the problem. Unless there is another way of going about it, I'm not exactly sure though.