|
Set A set is a collection of objects or things. Each object in a set a member or element of that set.Size of a set is the number of members in the set. Example: The set of even numbers between 2 and 10 is of size 5:{2,4,6,8,10}. The set of primes between 2 and 10 is of size 4:{2,3,5,7}. Remember: Each member of set A belongs to A or is in the set A. A set can not have repeating member:{1,3,1,2}is not a set. Rearranging the order of the members does not change the set:{1,2,3}is same as{3,2,1}. Combinations Number of ways we can select n objects from a group of m distinct objects is m!/!). Example: Number of possible ways to pick 4 oscar nominations from a list of 50 movies is 50!/!)=50!/=50494847/24=230300. Remember: This does not apply if there are identical objects. Permutation of Objects The number of ways n distinct objects can be ordered is n. Example: Number of ways 6 people can from a queue is 6. Number of ways 5 different cars can be parked in 5 parking spaces is 5. Remember: | 
