Five data entry operators work at the data processing department of the Birmingham Bank. Each day for 30 days, the number of defective records in a sample of

350

records typed by these operators has been noted, as follows:

Sample No.	No. Defectives	Sample No.	No. Defectives	Sample No.	No. Defectives
1	8	11	5	21	18
2	4	12	4	22	11
3	20	13	16	23	5
4	10	14	4	24	6
5	12	15	12	25	14
6	8	16	9	26	11
7	11	17	11	27	14
8	8	18	5	28	5
9	6	19	19	29	11
10	13	20	16	30	2

a) Establish 3

upper and lower control limits.

UCLp = (enter your response as a number between 0 and 1, rounded to three decimal places).

LCLp = (enter your response as a number between 0 and 1, rounded to three decimal places).

b) Why can the lower control limit not be a negative number?

.

c)Since the percent of defective records cannot be a negative number.

Since the upper control limit is positive.

C.

Since the upper control limit cannot be a negative number.

D.

Since the percent of defective records is always a positive number.

c) The industry standard for the upper control limit is 0.10. What does this imply about Birmingham Bank's own standards?

The industry standard is

not as strict as

the standard at Birmingham Bank.