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A Process That Is Considered To Be In Control Measures An Ingredient In Ounces. Below Are The Last

- A process that is considered to be in control measures an ingredient in ounces. Below are the last 10 samples (each of size n=5) taken. The population process standard deviation, , is 0.75.

Sample |
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1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |

15 |
14 |
17 |
15 |
13 |
15 |
14 |
16 |
13 |
17 |

14 |
15 |
13 |
16 |
14 |
14 |
17 |
15 |
14 |
12 |

13 |
16 |
14 |
13 |
16 |
16 |
15 |
13 |
16 |
16 |

14 |
13 |
16 |
15 |
15 |
12 |
16 |
15 |
12 |
13 |

12 |
15 |
15 |
12 |
13 |
13 |
13 |
14 |
15 |
15 |

- What is the ?
- If z=3, what are the control limits for the mean chart?
- What are the control limits for the range chart?

- The results of an inspection of DNA samples taken over the past 10 days are given below. Sample size is 100.

Day |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |

Defectives |
10 |
6 |
4 |
5 |
6 |
4 |
8 |
5 |
3 |
9 |

- Determine the 3-sigma p-chart control limits using this information.
- Using the control chart in part (a), and finding that the number of defectives on days 11, 12, and 13 are 8, 12, and 6, respectively, is the process in control?

- Twelve samples, each containing five parts, were taken from a process that produces steel rods. The length of each rod is the sample was determined. The results were tabulated and sample means and ranges were computed.

Sample |
Sample Mean (in.) |
Range (in.) |

1 |
10.001 |
0.011 |

2 |
10.003 |
0.014 |

3 |
9.996 |
0.006 |

4 |
10.006 |
0.022 |

5 |
9.996 |
0.009 |

6 |
9.999 |
0.008 |

7 |
10.003 |
0.008 |

8 |
10.004 |
0.014 |

9 |
9.997 |
0.005 |

10 |
10.002 |
0.01 |

11 |
10.004 |
0.011 |

12 |
10.005 |
0.009 |

- Determine the upper and lower control limits and the overall means for -chart and R-chart.
- Chart the charts and plot the values of the sample means and ranges.
- Does the data indicate a process that is in control? Why or why not?

Answer 1: sample 1 2 3 4 5 6 7 8 9 10 15 14 17 15 13 15 14 16 13 17 14 15 13 16 14 14 17 15 14 12 13 16 14 13 16 16 15 13 16 16 14 13 16 15 15 12 16 15 12 13