Consider the data set shown in Table 18.5.5, summarizing recent numbers of errors in batches of 500 invoices.
a. Find the percentage, p, for each batch.
b. Find the average percentage, .
c. Find the center line for the percentage chart.
d. Find the control limits for the percentage chart.
e. Draw the percentage chart.
f. Comment on what you see in the percentage chart. In particular, is this process in control? How do you know?
g. Write a paragraph, as if to your supervisor, summarizing the situation and defending the action you feel is appropriate.

Transcribed Image Text:

TABLE 18.5.5 Summaries of Defective Invoices in 25 Batches of n # 500 Number Batch Number Batch Identification of Errors, Identification of Errors, Number Number 14. 15 51 54 47 52 50 58 57 57 53 53 74 18 19 20 21 56 10 54 56 54 50 60 67 23 12 25 13