Project 73
Project description

With the simplifying assumption that that this data set represents approximately a simple random sample of all pennies in circulation in Tacoma, Washington in the summer of 2008, find a 95% confidence interval for the proportion of such pennies minted before 1982.

Background on the data set
This data set consists of the years and masses of 100 randomly selected pennies (from a piggy bank in Tacoma, Washington), the masses being measured to the hundredth of a gram. The measurements were made one evening during the summer of 2008 using a MyWeigh Durascale (50 g by 0.01 g capacity). The order of the pennies in the data set is the order in which their masses were measured (which was randomly determined). The two variables and their units are summarized in the following table.
Variables in the data set
The variables in the data set are as follows:
yearyearsyear in which the penny was minted
massgramsmass of the penny
Link to the data set
The full data set in csv format is at: