题目内容：

对某班50人进行智力测验,其得分如下:

48,64,52,86,71,48,64,41,86,79,71,68,82,84,68,64,62,68,81,57,90,52,74,73,56,78,47,66,55,64,56,88,69,40,73,97,68,56,67,59,70,52,79,44,55,69,62,58,32,58.

(1)这次测试成绩的最大值和最小值各是多少?

(2)将[30,100)平分成7个小区间,试画出该班学生智力测验成绩的频数分布图.

(3)分析这个频数分布图,你能得出什么结论?