1/13
P(E/F)=P(E&F)/P(F)=(1/49)/(13/49)=1/13
所有跟帖:
• The answer only for 7 families.n families is (n-1)/(7n-1) -jinjing- ♀ (24 bytes) () 06/01/2010 postreply 11:13:51
• The answer only for 7 families.n families is (n-1)/(7n-1) -jinjing- ♀ (24 bytes) () 06/01/2010 postreply 11:13:51