There are 10 students of which three are graduates. If a committee of five is to be formed, What is the probability that there are i. only 2 graduates ii. At least 2 graduates?
The chance that four students A, B, C ,D solve a problem are 1/2 , 1/3,1/4,1/4 respectively. If all of them try to solve a problem, what is the probability that the problem is solved?