Answer to Question #111190 in Statistics and Probability for Nimra

Question

Find the permutation of 4 objects A,B,C,D taken 2 at a time?

Answer 1

$\text{Number of results:}\\ \\p^n_{r}\implies p^4_{2}=12\\ \text{These results are:}\\ (A,B),(A,C),(A,D),(B,A),(B,C),(B,D),\\ (C,A),(C,B),(C,D),(D,A),(D,B),(D,C)$