45 students are not partticipating
Step-by-step explanation:Number of students that participated in school play = 30
% of students not participating = 60%
% of those participating = 100% - 60%
% of those participating = 40%
let the total number of students in 7th graders = y
Number of students that participated in school play = total number of students in 7th graders × % of those participating
30 = y × 40%
30 = y × 0.4
30 = 0.4y
divide both sides by 0.4:
Number of students not participating = total number of students in 7th graders - Number of students that participated in school play
Number of students not participating = 75 - 30
Number of students not participating = 45