5040
Step-by-step explanation:
There are 7 options for the 1st song, 6 options for the 2nd song, 5 options for the 3rd song, 4 options for the 4th song, 3 options for the 5th song, 2 options for the 6th song, and 1 option for the 7th song. We get:
(Note: when you have a number n, where it is multiplied by every number until one (ex. 7. Â Â 7*6*5*4*3*2*1), then the number in the result is n! (n factorial). So we get that 7*6*5*4*3*2*1 is 7! is 7 factorial. So 5040 is 7! )