Question

Each value represents the number of mistakes (defects) found on a student loan application. Values for 50 consecutive loan applications are given. Calculate the appropriate centerline and 3-sigma control limits for the c-chart, and then plot the data and create a control chart. Does the process appear to be in a state of statistical control? Why or why not?

Upper control limit (UCL) =

Centerline (CL) =

Lower control limit (LCL) =

Process in statistical control?

Medical Devices Variables

Sample	1	2	3	4	5	6	7
1	146.5	149.3	150.1	151.0	146.3	152.4	144.7
2	147.3	151.9	144.2	146.6	149.4	152.9	156.4
3	146.0	150.0	146.5	146.7	150.1	153.8	146.5
4	148.1	153.4	147.0	155.4	151.7	145.9	150.7
5	148.9	153.0	142.8	155.9	150.6	158.9	154.0
6	148.0	146.3	148.4	154.5	151.0	152.0	154.4
7	151.0	145.7	150.6	152.8	154.0	145.7	156.9
8	151.3	152.7	151.8	145.5	147.7	153.7	154.2
9	150.5	149.9	149.5	155.0	143.9	151.7	153.3
10	147.5	148.4	146.3	148.0	144.1	140.2	139.7
11	148.3	149.0	152.7	150.5	150.8	145.5	155.0
12	148.6	145.4	152.5	151.9	152.0	146.0	147.0
13	149.6	152.6	147.6	147.3	146.3	149.6	147.3
14	150.7	149.8	148.8	147.9	150.5	145.4	144.4
15	148.2	151.7	156.9	154.1	148.6	148.3	144.7
16	151.4	144.5	157.7	155.4	151.9	149.3	153.3
17	151.2	146.0	151.2	145.4	156.9	143.3	152.2
18	146.3	129.0	167.8	152.3	160.0	151.8	150.4
19	150.3	151.1	139.2	151.7	148.1	150.7	153.4
20	155.7	143.6	161.9	143.9	154.5	156.5	151.9

Answer 1

Sample	1	2	3	4	5	6	7	Xbar	Xbarbar	LCL	UCL	S.D	1.70932
1	146.5	149.3	150.1	151	146.3	152.4	144.7	148.6143	149.9029	144.7749	155.0308
2	147.3	151.9	144.2	146.6	149.4	152.9	156.4	149.8143	149.9029	144.7749	155.0308
3	146	150	146.5	146.7	150.1	153.8	146.5	148.5143	149.9029	144.7749	155.0308
4	148.1	153.4	147	155.4	151.7	145.9	150.7	150.3143	149.9029	144.7749	155.0308
5	148.9	153	142.8	155.9	150.6	158.9	154	152.0143	149.9029	144.7749	155.0308
6	148	146.3	148.4	154.5	151	152	154.4	150.6571	149.9029	144.7749	155.0308
7	151	145.7	150.6	152.8	154	145.7	156.9	150.9571	149.9029	144.7749	155.0308
8	151.3	152.7	151.8	145.5	147.7	153.7	154.2	150.9857	149.9029	144.7749	155.0308
9	150.5	149.9	149.5	155	143.9	151.7	153.3	150.5429	149.9029	144.7749	155.0308
10	147.5	148.4	146.3	148	144.1	140.2	139.7	144.8857	149.9029	144.7749	155.0308
11	148.3	149	152.7	150.5	150.8	145.5	155	150.2571	149.9029	144.7749	155.0308
12	148.6	145.4	152.5	151.9	152	146	147	149.0571	149.9029	144.7749	155.0308
13	149.6	152.6	147.6	147.3	146.3	149.6	147.3	148.6143	149.9029	144.7749	155.0308
14	150.7	149.8	148.8	147.9	150.5	145.4	144.4	148.2143	149.9029	144.7749	155.0308
15	148.2	151.7	156.9	154.1	148.6	148.3	144.7	150.3571	149.9029	144.7749	155.0308
16	151.4	144.5	157.7	155.4	151.9	149.3	153.3	151.9286	149.9029	144.7749	155.0308
17	151.2	146	151.2	145.4	156.9	143.3	152.2	149.4571	149.9029	144.7749	155.0308
18	146.3	129	167.8	152.3	160	151.8	150.4	151.0857	149.9029	144.7749	155.0308
19	150.3	151.1	139.2	151.7	148.1	150.7	153.4	149.2143	149.9029	144.7749	155.0308
20	155.7	143.6	161.9	143.9	154.5	156.5	151.9	152.5714	149.9029	144.7749	155.0308

Upper control limit (UCL) = mean + (3* SD )

Centerline (CL) = mean

Lower control limit (LCL) =mean - (3* SD )

where SD : standard deviation.

From the table we say that there is no point which is out of control means there is no point which lies upper the UCL or below the LCL hence we say that process is in control..

Thank You..!!