C nr represents the number of combinations of n items taken r at a time. With 6 5 4 3 2 1 which gives you 720. In how many ways can we do so.
For a combination the order does not matters.
Number of ways of choosing 5 cars 100 C 5 Hence the answer is 100 C 5. Combination of Functions Just as numbers can be added subtracted multiplied and divided new functions can be created by applying these same operations. In how many ways can we do so. However in permutations the order of the selected items is essential.