Permutations and Combinations
From a committee of persons, in how many ways can we choose a chairman and a vice chairman assuming one person can not hold more than one position?
Solution: From a committee of person, a chairman and a vice chairman are to be chosen in such a way that one person cannot hold more than one position.
Here, the number of ways of choosing a chairman is the permutation of different objects taken at a time.
Thus, required number of ways=