Problem 113SE

A manufacturer of coil springs is interested in implementing a quality control system to monitor his production process. As part of this quality system, it is decided to record the number of nonconforming coil springs in each production batch of size 50. During 40 days of production, 40 batches of data were collected as follows:

Read data across and down.

Solution:

Step 1 of 4:

The number of nonconforming coil springs in each production batch is given.

9 |
12 |
6 |
9 |
7 |
14 |
12 |
4 |
6 |
7 |

8 |
5 |
9 |
7 |
8 |
11 |
3 |
6 |
7 |
7 |

11 |
4 |
4 |
8 |
7 |
5 |
6 |
4 |
5 |
8 |

19 |
19 |
18 |
12 |
11 |
17 |
15 |
17 |
13 |
13 |

- We have to construct a stem-and-leaf plot of the data.
- We have to find the sample mean and sample standard deviation.
- We have to construct and interpret a time series plot of the data.