umm, yeah, i already knew that. but why?
I - Top 4 are more than X means that X could be in the 5th or 6th, or even in the remaining 153
II - with simple maths 4.8 could be adjusted in the lower 5 of the top 6 or anywhere in remaining 153
I & II - 67.8 - 56 = 11.8 which is 5th + 6th. X can be 6th with 4.8 or below 6th with 5th and 6th being 5.9 and 5.9, or slightly off. thus insuff.