当前位置: 首页 > 问题分类 > 学历类考试 > 成考 > 问题详情
问题

(本题满分8分) 设有5封信及标号为1~5的5个信筒,将这5封信投入任意-个信筒是等可能的,求下列事件的概率. (1)A=“5个信筒里各有-封信”; (2)B=“4号信筒里只能投指定的-封信,其余信筒各-封信”.

参考答案
正确答案:

您可能感兴趣的试题
  • We sent the letter by airmail (以便他们能及时收到).

  • The government official said that the new tax rates would come into ______ (effective) from April.

  • We will agree to sign the new contract provided that you increase our salaries by 5%.

  • His______(refuse) to come to our wedding upset the new couple.