The math extracurricular activity group of a school conducted a special survey on "How much do you know about garbage classification" among the students of the school, and arranged several questionnaires in the following table:
( 1)40÷0.2=200;
(2)40+ 120+ 18+x=200
x=22，
m= 120÷200=0.6
n= 18÷200=0.09
So the answer is: 200, 0.6, 0.09.