#### The following measurements were recorded for the drying time, in hours, of a certain brand of latex paint.

## 3.4 |
## 2.5 |
## 4.8 |
## 2.9 |
## 3.6 |
---|---|---|---|---|

## 2.8 |
## 3.3 |
## 5.6 |
## 3.7 |
## 2.8 |

## 4.4 |
## 4.0 |
## 5.2 |
## 3.0 |
## 4.8 |

#### Assume that the measurements are a simple random sample.

#### (a) What is the sample size of the above sample?

#### (b) Calculate the sample mean for this data.

#### (c) Calculate the sample median.

#### (d) Plot the data by way of a dot plot.

#### (e) Compute the 20% trimmed mean for the above data set.

**SOLUTION:**

Part a

The sample size is 15.

Part b

Part c

Sample median is the 8th value, after the data is sorted from smallest to largest: 3.6.

Part d

A dotplot is shown below

Part e

After trimming total 40% of the data (20% highest and 20% lowest), the data becomes: 2.9, 3.0, 3.3, 3.4, 3.6, 3.7, 4.0, 4.4, 4.8

So. the trimmed mean is

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