Find the arithmetic mean of 4 and 12.

Options

A. `9`
B. `8`
C. `16`
D. `10`

Explanation

To find the arithmetic mean of 4 and 12, we can follow these steps:

### Step 1: Understand the formula for arithmetic mean
The arithmetic mean (average) of two numbers A and B is calculated using the formula:
\[ \text{Arithmetic Mean} = \frac{A + B}{2} \]

### Step 2: Identify the values of A and B
In this case, we have:
- \( A = 4 \)
- \( B = 12 \)

### Step 3: Substitute the values into the formula
Now, we substitute the values of A and B into the formula:
\[ \text{Arithmetic Mean} = \frac{4 + 12}{2} \]

### Step 4: Perform the addition
Next, we add the two numbers:
\[ 4 + 12 = 16 \]

### Step 5: Divide the sum by 2
Now, we divide the sum by 2 to find the arithmetic mean:
\[ \text{Arithmetic Mean} = \frac{16}{2} = 8 \]

### Final Answer
The arithmetic mean of 4 and 12 is:
\[ \boxed{8} \]

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