最新提问
我的动态
登录后查看动态
题目内容双击单词支持查询和收藏哦~
The average (arithmetic mean) number of passengers on a subway car is 60. If the number of passengers on a car has a normal distribution with a standard deviation of 20, approximately what percent of subway cars carry more than 80 passengers?
A显示答案
以上解析由 考满分老师提供。