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, she inspected 1,000 units of output from each machine in random samples, with the following results: Show your work.
Machine Total Defectives
1 23
2 15
3 29
4 13
What is the sample proportion of defectives for machine # 1?
A) .023
B) .02
C) .0115
D) .0058
E) .005