35% of the students voted for cake, and there are 42 of them.
so the ratio is 42:35
put it into this to solve this, assume there are x students in the school.
42 students :35% = x students: 100%
42:35=x:100
42/35=x/100
cross multiply them
35x=4200
x=120
thus, 120 6th graders are at Amanda's School.