Questions: Which of the following statements are true? Select all that apply.
The mean of Sample 2 underestimates the population mean.
The mean of Sample 1 underestimates the population mean.
The mean of Sample 2 overestimates the population mean.
The mean of Sample 2 equals the population mean.
The mean of Sample 1 overestimates the population mean.
The mean of Sample 1 equals the population mean.
Transcript text: Which of the following statements are true? Select all that apply.
The mean of Sample 2 underestimates the population mean.
The mean of Sample 1 underestimates the population mean.
The mean of Sample 2 overestimates the population mean.
The mean of Sample 2 equals the population mean.
The mean of Sample 1 overestimates the population mean.
The mean of Sample 1 equals the population mean.
Solution
Solution Steps
To determine which statements about the means are true, we need to calculate the population mean and the means of the given samples. Then, we can compare the sample means to the population mean to see if they underestimate, overestimate, or equal the population mean.
Solution Approach
Calculate the population mean using the scores of all students.
Calculate the mean of Sample 1.
Calculate the mean of Sample 2.
Compare the sample means to the population mean to determine which statements are true.
Step 1: Calculate the Population Mean
The population mean is calculated using the scores of all students:
\[
\text{Population Mean} = \frac{97 + 81 + 78 + 55 + 98 + 84 + 93 + 87 + 61 + 98 + 100 + 92}{12} = 85.3333
\]
Step 2: Calculate the Mean of Sample 1
The mean of Sample 1 is calculated as follows:
\[
\text{Mean of Sample 1} = \frac{97 + 81 + 78 + 55 + 98 + 84}{6} = 82.1667
\]
Step 3: Calculate the Mean of Sample 2
The mean of Sample 2 is calculated as follows:
\[
\text{Mean of Sample 2} = \frac{93 + 87 + 61 + 98 + 100 + 92}{6} = 88.5000
\]
Step 4: Compare Sample Means to Population Mean
The mean of Sample 1 (\(82.1667\)) is less than the population mean (\(85.3333\)), so it underestimates the population mean.
The mean of Sample 2 (\(88.5000\)) is greater than the population mean (\(85.3333\)), so it overestimates the population mean.
Final Answer
\(\boxed{\text{The mean of Sample 2 overestimates the population mean.}}\)