hi,

you did not mention about any particular exam name, I assume you are asking about keam entrances test, i.e karnataka engineering agriculture and medical entrance exam. the rank list of keam is made by considering 12th score and score in keam test by giving the ratio of 50:50. since there is very few seats available for b.sc in agriculture competition is quite tough. however you have to give correct answers of more than 90% of questions to get a decent score and rank.