1. How many 2-digit numbers can be formed using only the digits 2, 3, 5, and 6, if the digits are not to be repeated within a number?

Question

I am confused please help

Answer 1

think about it:
1st digit: 4 choices
2nd digit: 3 choices left, for each of the four 1st digit choices.
So, what do you think

Study permutations. In this case, 4P2 = 4*3

Answer 2

thank you