Five data entry operators work at the data processing department of the Royal Bank. Each day for 30 days, the number of

defective records in a sample of 250 records typed by these opera- tors has been noted, as follows:

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

a) Establish 3s upper and lower control limits. b) Why can the lower control limit not be a negative number? c) The industry standards for the upper and lower control limits are 0.10 and 0.01, respectively. What does this imply about Royal Banks own standards?