ONE QUESTION, ONE STEP
ZX-561696D74FObservational studies and experiments · 第 5 题
Observational studies and experiments · 原库模块 1 · Q5 原库参考解析
To determine the mean number of children per household in a community, Tabitha surveyed 20 families at a playground. For the 20 families surveyed, the mean number of children per household was 2.4. Which of the following statements must be true?
参考答案：
解题思路
容易忽略的一步
