Since this is a SEO contest at IIIT Hyderabad and have to rank higher in search engines like Google, Bing and duckduckgo for SEOContestAtIIITHyderabad, we are going to see the importance of keyword-density or does it really matter much.
As a warning if google bots sees your post as just a piece of keyword packed content without any useful information for the visitors who eventually find your post because of your keywords, then be prepared for the wrath of panda.
The truth is "keyword" is indeed key for getting ranked higher for that it as Google sees, this post for eg: for SEOContestAtIIITHyderabad, it could be relevant for that keyword. But Google also monitors the visitors behavior and if it finds out there is nothing there in your post , then your post is out of SERP.
So as the old sayings "Content is the King" and if you got good relevant info on a particular keyword even if the its density is on the higher side and it's useful to the visitors then your post will rank higher automatically.
But what amount is too high or too low for a keyword count? Many say 3 to 5% of the total words of a page is fine. But if you want to play it safe like I do for SEOContestAtIIITHyderabad, you can stick with 4%.
At this point when I checked the count in MS Word, I had like 252 words and out of which I had SEOContestAtIIITHyderabad used 4 times including this one and 1 at the post topic and 1 at the url and probably 1 or 2 at the post description. So it amounts to 8 and 4% of 252 is 10. So I could say I'm still in the safe zone of not over using my keyword.
So lets just see if this kinda post really helps me in getting me ranked higher in SERP.
P.S: If you eventually end up writing a long post and way too much keyword without intentionally then try replacing some with other alternative word relevant to your niche.
Checkout my previous post SEOContestAtIIITHyderabad on commentluv plugin