DCE Entrance Examination and Mathematics Olympiads are always from Permutations and Combinations, and Probability, but the irony is that most of the students do not attempt them correctly., Permutations and Combinations Probability, Somitra Sanadhya & Vikash Tiwari, SP Neelam, Science Pyramid, Science Pyramid Mathematics, science and mathematics, statistics, Analysis, Higher Education Permutations, and Combinations Probability,