Take 286+126 then divide by 2, I think. it makes sense to me.
The song is 286 seconds, so if it is 126 seconds less than twice the first song, add 126 and you have twice the first song. Since you have twice the length of the first song divide by 2 and you have the length of the first song.
EDIT:
well if everyone else is giving you the answer, I might as well too. I just wanted to make you work a little.
412 is twice the length of short song, divided by two is 206. the shorter song is 206 seconds long.