Question 490296: can you please help me?
show all work, a disk jockey has 9 songs to play. 5 are slow, and 4 are fast. each song is to be played only once. in how many ways can the disc jockey play the 9 songs if:
-the songs can be played in any order
- the first two songs must be fast
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! a disk jockey has 9 songs to play. 5 are slow, and 4 are fast. each song is to be played only once.
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In how many ways can the disc jockey play the 9 songs if:
-the songs can be played in any order
Ans: 9! = 362,880 ways
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- the first two songs must be fast
4C2 = 6 ways to select 2 fast songs
2 ways to order the 2 fast songs selected
7! ways to arrange the remaining 7 songs
Ans: 6*2*7! = 60,480 ways
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Cheers,
Stan H.
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