According to your question as you have asked that how much marks required for  DU CET for journalism but your percentage is 73, so according to the experience it is still critical for you to get
admission there as yes it true that 50% is the minimum  as it is mentioned over there according to the eligibility criteria but as you have already heard about all this that it
is not easy to get admission just on the basis of entrance as students from
many places come here to give exam and also there are plenty of students who
have scored  90% or more than that , so
if you clear the exam then you will have undergo in the process of cut-off as
after your rank in the cut –off then it will be decided that whether you will
get admission or not. So I think you should not rely on this and have to go for
other options also and apply in other universities also as it is an integrated
course in DELHI UNIVERSITY so competition will going to be very tougher.