What is the formula to find the number of permutations to 4 sets of 6 numbers?

Jan 20, 2017

To find the possible ways to select four objects out a group of six, when order is important, you calculate

P(6,4) = (6!)/(2!) = 360

Explanation:

There is a variety of ways in which permutations are expressed. Here I am using $P \left(n , r\right)$ to mean the number of permutations of r objects selected from a group of n objects.

In general, permutations imply that it is important to note the order in which the selections are made. An example would be when people are to be selected from a class of students, with the first selection to be president, the next, vice-president and so on.

The number of permutations of r objects selected from n is found by

P(n,r)= (n!)/(n-r!)

P(6,4)= (6!)/(6-4!) = 720/2=360