If you want 85℅ of marks in your examination and you have been really working hard to achieve the score.
All you need to do is get that in a dream…. in other words, let the subconscious part of your mind accept the deal your conscious part of the brain is trying hard to crack.
So, first focus on the target (for the conscious half of brain) and second, have faith in yourself and your plan (for the subconscious part of the brain). Because no one else is going to do these two taks for you.
All I ask you is to get that in your dream.