Let x̅1 and x̅2 (where x̅2 > x̅1) be the means of two sets comprising n1 and n2 (wheren2 < n1) observations respectively. If x̅ is the mean when they are pooled, then which one of the following is correct?

• A. x̅1 < x̅ < x̅2
• B. x̅ > x̅2
• C. x̅ < x̅1
• D. (x̅1 – x̅) + (x̅2 – x̅) = 0