Question

a license plate begins with two letters. if the possible letters are A, B, C, D, and E, how many different ways of these letters can be made of if no letter is used more than once?

Answer 1

20

Explanation:

A, B, C, D, E is a set of 5 letters.

A letter can only be used once.

You have 5 choices for the first letter.

5

Since the letter that was selected to go first cannot be used again, now you have 4 choices for the second letter.

5 × 4

5 × 4 = 20

Answer: 20