If you failed in 12 th that is past and won't at all decide you future. If you put in all your hardwork and efforts you can crack any exam . And to put in this way the quants syllabus of CAT is till class 10 maths only . And For DILR nad VARC its all about practice. Keep on putting efforts and you will ace it .

You should definitely give it a try . What is in your hands in efforts . Give it your all without thinking about the results and in the end you will find that you have aced the exam and get into top B - school.