SOLUTION: Show all work. A disc jockey has 7 songs to play. 5 are slow songs, and 2 are fast songs. each song is to be played only once. In how many ways can the disc jockey play the 7 songs

Algebra ->  Probability-and-statistics -> SOLUTION: Show all work. A disc jockey has 7 songs to play. 5 are slow songs, and 2 are fast songs. each song is to be played only once. In how many ways can the disc jockey play the 7 songs      Log On


   

Question 574592: Show all work. A disc jockey has 7 songs to play. 5 are slow songs, and 2 are fast songs. each song is to be played only once. In how many ways can the disc jockey play the 7 songs if:
a)the songs can be played in any order
b)the first song must be a slow song and the last song must be a slow song
c)the first two songs must be fast songs
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A disc jockey has 7 songs to play. 5 are slow songs, and 2 are fast songs. each song is to be played only once. In how many ways can the disc jockey play the 7 songs if:
a)the songs can be played in any order:: 7! = 5040
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b)the first song must be a slow song and the last song must be a slow song
1st song: 5
last song: 4
middle 5 songs: 5!
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# = 5*4*5! = 20*120 = 2400
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c)the first two songs must be fast songs
1st 2 songs: 2
last 5 songs: 5!
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# = 2*120 = 240
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Cheers,
Stan H.
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