In the AAI formula, the denominator is 2n. Which option correctly reflects this?

• A. 2n
• B. n
• C. n+1
• D. 2n+1

Answer: (A)

The key idea here is that the quantity being averaged or balanced involves two equal parts, each with n terms. When you account for both parts, the total number of terms is 2n, so the denominator must be 2n. This matches the form that divides by twice the count of terms, giving the proper average across both sides. The other options would imply either only counting one side (n) or adding an extra term (n+1 or 2n+1), which would change the value and not reflect the intended denominator.