mid-value of class interval

• 组中值

mid-value of class interval的用法和样例：

例句

1. Rolle's theorem is a special case of the mean value theorem.
   罗尔定理是中值定理的一种特殊形式。
2. Class midpoint and chronological average both are one of the most important concepts in statistics.
   组中值与序时平均数是统计学中的两个重要概念。