2) 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 operators 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

Establish 3 upper and lower control limits.

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

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?