In this video tutorial I show you how to calculate how many arrangements or permutations when letters or items are restricted to the ends of a line.
The following examples are given with worked solutions.
1) In how many ways can 2 men and 3 women sit in a line if the men must sit on the ends?
2) In how many ways can 3 blue books and 4 red books be arranged on a shelf if a red book must be on each of the ends assuming that each book looks different except for colour.