IPhone memory. I have 4.6 GB left. How many songs can I fit on here?

Would I be able to sync 728 songs? Some opinions would be great! I've already tried syncing them and almost 300 songs won't transfer from iTunes to my iPhone.
Does that sound at all right?

Depends on the size of the mp3 file. That could be right

If my calculations are correct you should be able to get over 800 songs with 4.6GB free.