A Quality Analyst wants to construct a control chart for determining whether four machines, all producing the same product, are under control with regard to a

particular quality attribute. Accordingly, the analyst inspected $1,000$ units of output from each machine in random samples, with the following results:

$\backslash$table$[[$Machine$,$Total Defectives$],[$#$1,23],[$#$2,15],[$#$3,2?$