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?

Adrian can put a total of 1716 combinations in the player. 

The formula to be used is as follows:

total combinations = n!/[r! *(n-r)!]
n = number of disks available  = 13
r = number of disks that be held = 6

= 13! = (13• 12•11•10•9•8•7•6•5•4•3•2•1)/(6! • 7!)
=1716

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i believe it's a.

i'm not sure on this one, most likely correct.

good luck!