A die is thrown .If the number shown is even, what is the probability that it is getting greater than 3?
分析:obviously 答案是2/3
但記得yll曾出一條概率問題,
http://yll.loxa.edu.tw/phpBB2/viewtopic.php?t=2706
當中提及條件概率,和這situation相類似,
那麼答案是P(B|A)=P(A&B)/P(A)=(2/3)/(1/2)=1/3嗎?