Question

How many permutations of {a,b,c,d,e,f,,g}end with a?

Short answer

The resultant answer is 720 .

Step-by-step solution

Given data

The given data is {a,b,c,d,e,f,g} .

Concept of Permutation

A permutation of {a,b,c}is the listing of the three elements in the set in any order (without repeating any of the elements).

Find the permutation

The first letter of the permutation can be any letter of the set {a,b,c,d,e,f,g} except a, so there are 6 possible permutations of the first letter. The second letter of the permutation can be any letter except the first letter and a, so there are 5 possible permutations of the second letter. This pattern continues through all the letters of the set, with a being the last letter of the permutation.

6! = 6 . 5. 4 . 3 . 2 . 1

= 720