Question

Adrian's CD player can hold six disks at a time and shuffles all of the albums and their songs. If he has thirteen CD's, how many different combinations of six CD's can he put in the player?
A. 8,648,640

B. 1,716

C. 5,040

D. 720

Answer 1

To answer this problem, the utilization of the provided formula is of utmost importance.

The formula to be used would be for the combination with no repetition since it is what is asked and possibly happens when involving the products mentioned in the problem. The formula would be

      n!                                              where in
-------------                                                   n = number of things to choose from
(n - r)! r!                                                      r = number of things needed to form

the symbol ! is called a factorial function which replaces the sequence of multiplying a number in a descending order.

lets substitute and solve

      13!
--------------
(13 - 6)! 6!

      13!
-------------
   (7!) 6!

6,227,020,800
-------------------
  5,040 x 720

6,227,020,800
-------------------
    3,628,800

1,716

The answer would be 1,716.