The number of possible arrangements of pictures she can hang on her wall is 120.
The number of possible arrangements can be determined by dividing the factorial of 6 by the factorial of 3.
Number of possible arrangements = 6! / 3!
( 6 x 5 x 4 x 3 x 2 x 1) / (3 x 2 x 1) = 6 x 5 x 4 = 120
To learn more about combination, please check: https://brainly.com/question/13387529
#SPJ2