One advantage of a stem and leaf plot over a frequency distribution is that （）.

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

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

對某班級學(xué)生的生活狀況進行統(tǒng)計調(diào)查，下列標(biāo)志中屬于不變標(biāo)志的是（）

品合格率指標(biāo)是（）

什么是季節(jié)變動？研究它的意義何在？如何測定季節(jié)變動？

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

為什么在計算平均指標(biāo)的基礎(chǔ)上還有必要進一步計算變異指標(biāo)？

Descriptive statistics deals with methods of（）

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 （）.