Find Number Groups with Mean = 5: Average Value Problem

To solve this problem, we'll follow these steps:

• Step 1: Identify the groups and calculate the average for each.

• Step 2: Compare the calculated averages with 5.

Now, let's apply these steps:
Step 1: - For choice (a), the group is $\{5\}$. The average is $\frac{5}{1} = 5$.
- For choice (b), the group is $\{5, 0\}$. The average is $\frac{5 + 0}{2} = \frac{5}{2} = 2.5$.
- For choice (c), the group is $\{5, 5, 5\}$. The average is $\frac{5 + 5 + 5}{3} = \frac{15}{3} = 5$.

Step 2: The calculated averages for choices (a) and (c) are 5.

Therefore, the groups of numbers for which 5 is the average are choices (a) and (c).

Hence, the correct answer is Answers (a) and (c) are correct.