Math Fun Library

Question :
What is the connection between Permutation and Combination ?

Answer :
Permutation is an ordered arrangement of all or part of a set things.
For Example all possible permutations of the letters a, b and c are :
a, b, c, ab, ac, ba, bc, ca, cb, abc, bac, cab and cba.
Combination of a set of objects is any selection of one or more of the objects without regard to order.
The number of combinations of n things r at a time is the number of sets that can be made up from the n things, each set containing r different things and no two sets containing exactly the same r things. This is equal to the number of permutations of the n things taken r at a time, divided by the number of permutations of r things taken n at a time.
In general, Permutation means arrangement of things. The word arrangement is used, if the order of things is considered. Whereas, Combination means selection of things. The word selection is used, when the order of things has no importance.