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

If the individual class frequency is divided by the total frequency, the result is the （）.

最能反映離散程度的指標(biāo)是（）

The number of phone calls arriving at a switchboard each hour has been recorded and the following frequency distribution has been developed.What is the cumulative frequency of the third class？（）

A cumulative frequency distribution would provide（）.

對(duì)某班級(jí)學(xué)生的生活狀況進(jìn)行統(tǒng)計(jì)調(diào)查，下列標(biāo)志中屬于不變標(biāo)志的是（）

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 （）.

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 （）.

某企業(yè)的生產(chǎn)計(jì)劃完成百分比采用如下分組，請(qǐng)指出哪項(xiàng)是正確的（）

某廠某年職工勞動(dòng)生產(chǎn)率為20000元，是歷史最高水平的1.2倍。這里的1.2倍是（）