If a Reading club has nine members, how many ways can all nine members line up for a picture?
- PuzzlingLv 74 weeks ago
In general, if there are n items, the total ways to arrange (permute) them is n!
The long way is to think:
You have 9 choices for the person in the first position.
You have 8 choices for the person in the second position.
You have 7 choices for the person in the third position.
You have 2 choices for the person in the eighth position.
You have 1 choice for the person in the last position.
Multiply those together:
9 * 8 * 7 * 6 * 5 * 4 * 3 * 2 * 1
= 362,880 ways