如果居民按報(bào)告期價(jià)格購買商品需多支出40萬元，報(bào)告期商品銷售額為200萬元，則價(jià)格指數(shù)為（）

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

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

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 approximate range of the number of phone calls arriving each hour？（）

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

Which of the following statements is not true？（）

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 （）.

最能反映離散程度的指標(biāo)是（）

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

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（）