dent who wants to buy 3 CDs, but assume that there are 4 CDs featuring the piano, 6 CDs featuring the trumpet, and 7 CDs featuring the saxophone.

(1) In how many different ways can the 3 CD's be selected?


(2) In how many ways can the selection be made if CD's featuring at least 2 different instruments are selected?

1-

4+6+7=17
17-3=14

17!/14!
=680