概率论作为数学的一个分支,经常能解释日常生活中的一些问题．我们根据直觉或常识对可能性做出的判断,大多数情况下是可靠的．然而有些时候,事实上的可能性与人们的想象却又相差得很远,有时会令人很吃惊．一、生日问题如果你的班上有40人,会有同学在同一天过生日吗?你可能会想:一年365天,40个人中有两人生日相同几乎是不可能的．事实上,我们按一年有365天算,两个人生日不在同一天的概 As a branch of mathematics, probability theory can often explain some problems in daily life. Our judgments about the possibilities based on intuition or common sense are reliable in most cases. However, in some cases, the actual possibility is far from people’s imagination, and it is sometimes surprising. First, birthday questions If your class has 40 people, will there be classmates on the same day birthday? You may think: 365 days a year, two of the 40 people in the same birthday is almost impossible. In fact, we count 365 days a year, and two people’s birthdays are not on the same day.