The results of inspection of DNA samples taken over the past

The results of inspection of DNA samples taken over the past 10 days are given balow. Sample size is 100 Day 10 a) The upper and lower 3-sigms control chart limits are: UCLter your reeponse se a number between 0 and 1, rounded to three decimal plsces) LCLp(enter your response as a number bstween 0 and 1, rounded fo three decimal piaces) b) Given the limits in part a, is the process in control for the follawing days as shawn in the lable below? Day Number of Defects In Control 12 13

Solution

Day

1

2

3

4

5

6

7

8

9

10

Defectives

7

9

9

11

7

8

0

11

13

2

Mean of defectives = (7+9+9+11+7+8+0+11+13+2)/10 = 7.7

UCL = Mean + 3*mean = 7.7 + 3 *7.7=7.7+8.32=16.02

LCL = Mean - 3*mean = 7.7 - 3 *7.7=7.7+8.32=-0.62

Answer B:-

Day

Defectives

In control

11

9

Yes as it lies within UCL

12

7

Yes as it lies within UCL

13

11

Yes as it lies within UCL

Day	1	2	3	4	5	6	7	8	9	10
Defectives	7	9	9	11	7	8	0	11	13	2