Ex 6.3,5 - Chapter 6 Class 11 Permutations and Combinations

Transcript

Ex 6.3, 5 (Method 1) From a committee of 8 persons, in how many ways can we choose a chairman and a vice chairman assuming one person cannot hold more than one position? We need to choose a chairman & a vice-chairman out of 8 person Here n = Number of people = 8 & r = Number of people to be chosen = 2 Number of ways choosing a vice-chairman = 8P2 = 8!/(8 2)! = 8!/6! = (8 7 6!)/6! = 8 7 = 56 ways Ex7.3, 5 (Method 2) From a committee of 8 persons, in how many ways can we choose a chairman and a vice chairman assuming one person cannot hold more than one position? We need to choose a chairman & a vice chairman out of 8 person Number of ways we can choose = 8 7 = 56 ways