Question

The manager of the Paper Department shows up at your office asking for help.

Part A. She has collected the data in Dataset #2 but is unsure whether she wants a p chart or an np chart. She is hoping you can do both and show her how they look.

Part B. She also hopes that you have time to set up an incoming inspection plan for her. She doesn’t like the number of bad items coming from the Rock Dept. and wants to set up a single sample inspection plan. She wants the Probability of Acceptance to be 95% for lots with a reject rate of 0.05 and the Probability of Acceptance to be 10% for lots with a fraction defective of 0.15. (Need further help/elaboration on Part B)

Day	Sample (n)	Number (np)	Proportion (p)
1	500	12	0.024
2	500	15	0.030
3	500	19	0.038
4	500	13	0.026
5	500	9	0.018
6	500	26	0.052
7	500	18	0.036
8	500	14	0.028
9	500	17	0.034
10	500	18	0.036
11	500	16	0.032
12	500	24	0.048
13	500	11	0.022
14	500	31	0.062
15	500	16	0.032
16	500	10	0.020
17	500	16	0.032
18	500	17	0.034
19	500	20	0.040
20	500	15	0.030
21	500	8	0.016
22	500	13	0.026
23	500	12	0.024
24	500	17	0.034
25	500	18	0.036

Answer 1

t These data will be used to construct a P control chart. chart. The subgroup size = asoo The. P values for each subgroup (day) have been calculated and and are shown table. For example for day I there were 12 defective item (Ap) found in the 500 innoile sample thur PE npla 12/5oo 0.024 The P value for the other days are calculated similarly Averages and control limit. The next step is to calculate the average fraction defective The sum of the 387 The frum of the n value 125oo The average is then calculated as Show below np value P = Inpa In Add up all the np value Add upp all the n value 387 03096 = 12500 Add up all the A value 3.096% m= zn # K- 12500 25 no of day 500