Just to make it alittle more complicated :
1446 isn't right either.
when I've got 160 playlist with 1449 songs alltogether, this means there's an average of 1449/160=9.05625 songs per playlist.
let's assume 9 playlists with 10 songs and 151 with 9 songs.
in the playlists with 10 songs there are 7 possible combinations and in the ones with 9 songs there are 6
So 9*9 + 151*6 = 987.

The above number is correct under the assumption that there are 9 lists with 10 and 151 lists of 9 songs though.
To be completely accurate you should first find all possible solutions of fitting 1449 songs in 160 playlists, then calculate the number of groups of four they can contain and calculate the average.


Frank van Gestel