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

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


   

Question 424256: Show all work. A disc jockey has 7 songs to play. Three are slow songs, and four are fast songs. Each song is to be played only once. In how many ways can the disc jockey play the 7 songs if
• The songs can be played in any order.
• The first song must be a slow song and the last song must be a slow song.
• The first two songs must be fast songs.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
7 songs to play.
Three are slow songs, and
four are fast songs.
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Each song is to be played only once.
In how many ways can the disc jockey play the 7 songs if
• The songs can be played in any order:::7! = 5040 ways
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• The first song must be a slow song and the last song must be a slow song.
1st song: 3 ways
last song: 2 ways
Middle 5 songs: 5! = 120 ways
Total ways: 3*2*120 720 ways
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• The first two songs must be fast songs.
1st song: 4 ways
2nd song: 3 ways
last 5 songs: 5! = 120
Total ways:4*3*120 = 1440 ways
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Cheers,
Stan H.
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