题干

我国是世界上严重缺水的国家之一.为了倡导“节约用水从我做起”,小刚在他所在班的50名同学中,随机调查了10名同学家庭中一年的月均用水量(单位:t),并将调查结果绘成了如下的条形统计图
(1)求这10个样本数据的平均数、众数和中位数;
(2)根据样本数据,估计小刚所在班50名同学家庭中月均用水量不超过7 t的约有多少户.

上一题 下一题 0.0难度 选择题 更新时间:2019-08-30 12:29:43

答案(点此获取答案解析)

(1)观察条形图,可知这组样本数据的平均数是:
x-=6×2+6.5×4+7

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