While attending a film festival you decide that there are 13 movies that you are interested in seeing. However, you only have time to see 7 movies. In how
many different ways can you watch 7 of the 13 movies?
A.
665,280

B.
8,648,640

C.
13

D.
4,324,320

Respuesta :

permutaions or the slot method

7 slots
13 choies

1st slot: 13 choices
2nd slot: 12 choices (1 less)
3rd slot: 11 choices (1 less)
4th slot: 10 choices (1 less)
5th slot: 9 choices (1 less)
6th slot: 8 choices (1 less)
7th slot: 7 choices (1 less)

so ways is 13*12*11*10*9*8*7=8648640 ways


B is answer