Chin researched the amount of money 150 students earned per month from jobs held during the summer. He created a table of six sample means from his collected data.

\begin{tabular}{|c|c|}
\hline
Sample Number & Sample Mean (\$) \\
\hline
1 & 208 \\
\hline
2 & 235 \\
\hline
3 & 245 \\
\hline
4 & 207 \\
\hline
5 & 205 \\
\hline
6 & 210 \\
\hline
\end{tabular}

Using his results, what is a valid prediction about the mean of the population?

A. The predicted mean of the population will be less than 200.
B. The predicted mean of the population will be less than 245.
C. The predicted mean of the population will be more than 275.
D. The predicted mean of the population will be more than 250.



Answer :

Let's walk through the solution step-by-step using the data provided in the table:

1. Collect the sample means:
The means from the six samples are:
- Sample 1: 208
- Sample 2: 235
- Sample 3: 245
- Sample 4: 207
- Sample 5: 205
- Sample 6: 210

2. Calculate the average of the sample means:
To find the predicted mean of the population, we first need to calculate the average of the sample means.

We sum all the sample means:
[tex]\[ 208 + 235 + 245 + 207 + 205 + 210 = 1310 \][/tex]

Then, we divide this sum by the number of samples (which is 6):
[tex]\[ \text{Average (Predicted Mean)} = \frac{1310}{6} = 218.33333333333334 \][/tex]

3. Interpret the predicted mean:
The calculated average (predicted mean) is approximately [tex]\(218.33\)[/tex]. Now, we need to determine which of the provided predictions aligns with this value:

- The predicted mean of the population will be less than 200.
- The predicted mean of the population will be less than 245.
- The predicted mean of the population will be more than 275.
- The predicted mean of the population will be more than 250.

4. Choose the correct prediction:
- [tex]\(218.33\)[/tex] is not less than 200.
- [tex]\(218.33\)[/tex] is less than 245.
- [tex]\(218.33\)[/tex] is not more than 275.
- [tex]\(218.33\)[/tex] is not more than 250.

Therefore, the valid prediction about the mean of the population is:

The predicted mean of the population will be less than 245.