Question

If no digit may be used more than once, how many 2-digit numbers can be formed using only the digits 5, 6, 3, and 2?

Answer 1

4 choices for each digit, so 4*4 values

Answer 2

The answers are:

11
12
10
2

Answer 3

My bad. I thought I read that digits could be repeated. So, the answer is 4*3 = 12