A previous report from a government organization indicates that smokers, on average, miss 6.26 days of work per year due to sickness (including smoking-related acute and chronic conditions). Nonsmokers miss an average of 3.76 days of work per year. If two years later the organization believes that the average days of work missed by smokers has not changed, it could confirm this by sampling.

Consider the sample shown below. Determine the sampling error of this sample, assuming that the organization's supposition is correct.

[tex]\[
\begin{tabular}{rrrrrrrrrrrr}
\hline 2 & 0 & 0 & 6 & 12 & 9 & 11 & 5 & 9 & 4 & 11 & 11 \\
8 & 0 & 1 & 4 & 10 & 4 & 2 & 6 & 6 & 11 & 1 & 7 \\
2 & 8 & 1 & 8 & 2 & 6 & 2 & 1 & 4 & 9 & 7 & 5 \\
\hline
\end{tabular}
\][/tex]

(Round to three decimal places as needed.)



Answer :

To determine the sampling error of the sample, assuming the organization's supposition about the population mean (6.26 days) is correct, follow these steps:

### Step 1: Collect the Data
We have the following data points representing the number of days missed by smokers:

[tex]\[ \begin{array}{rrrrrrrrrrrr} 2 & 0 & 0 & 6 & 12 & 9 & 11 & 5 & 9 & 4 & 11 & 11 \\ 8 & 0 & 1 & 4 & 10 & 4 & 2 & 6 & 6 & 11 & 1 & 7 \\ 2 & 8 & 1 & 8 & 2 & 6 & 2 & 1 & 4 & 9 & 7 & 5 \\ \end{array} \][/tex]

### Step 2: Calculate the Sample Mean
To find the sample mean, sum all the data points and then divide by the number of data points.

We sum the data points:

[tex]\[ 2 + 0 + 0 + 6 + 12 + 9 + 11 + 5 + 9 + 4 + 11 + 11 + 8 + 0 + 1 + 4 + 10 + 4 + 2 + 6 + 6 + 11 + 1 + 7 + 2 + 8 + 1 + 8 + 2 + 6 + 2 + 1 + 4 + 9 + 7 + 5 = 195 \][/tex]

Next, we count the total number of data points, which is 36.

Thus, the sample mean is:

[tex]\[ \bar{x} = \frac{195}{36} \approx 5.417 \][/tex]

### Step 3: Population Mean
According to the organization's report, the mean number of days missed by smokers is 6.26 days.

### Step 4: Calculate the Sampling Error
The sampling error is the difference between the sample mean and the population mean:

[tex]\[ \text{Sampling Error} = \bar{x} - \mu \][/tex]

Substituting the values we have:

[tex]\[ \text{Sampling Error} = 5.417 - 6.26 = -0.843 \][/tex]

### Step 5: Present the Final Answer
So, the sample mean and the sampling error are:

[tex]\[ \text{Sample Mean} \approx 5.417 \][/tex]

[tex]\[ \text{Sampling Error} \approx -0.843 \][/tex]

These results indicate that the sample mean is approximately 5.417 days, and the sampling error is approximately -0.843 days.