math!
posted by Celest .
IN MR.MAROLE'S CLAOF THE STUDENTS TAKE MUSICSS, THREE FOLESSONS.THAT IS, 15 STUDENTS TAKE MUSIC.HOW MANY STUDENTS ARE IN MR.MAROLE'S CLASs? explain.

I already answered this for you.
http://www.jiskha.com/display.cgi?id=1329949492