One rule that must always be followed in constructing frequency distributions is that （）.

If data are grouped into intervals and the number of items in each group is listed, this could be called a （）

某班的學(xué)習(xí)按考試成績分為60分以下，60-70，70-80，80-90，90-100，這種分組（）

Simon Arnett, Director of Human Resources, is exploring the causes of employee absenteeism at Buderim Bottling during the last operating year (1 January 2005 to 31 December 2005). The average number of absences per employee, calculated from the personnel data of all employees, is a （）.

企業(yè)生產(chǎn)一種產(chǎn)品需順次經(jīng)過四個車間，這四個車間的廢品率分別為1.5%、2.0%、2.0%和1.0%。該企業(yè)生產(chǎn)這種產(chǎn)品的平均廢品率是多少？

A student achieves an 82 on the first test in a statistics course. From this, she assumes that her average at the end of the semester (after other tests) will be about 82. This is an example of （）.

在組距數(shù)列中，下限就是（）

某企業(yè)的生產(chǎn)計劃完成百分比采用如下分組，請指出哪項是正確的（）

要了解某地區(qū)全部大學(xué)生的就業(yè)情況，那么（）

Which of the following is not the goal of descriptive statistics?（）