Of the 30 students participating in a science fair, 12 are growing plants, 8 are making modelvolcanoes, and the rest are doing other projects. What is the ratio of students doing other projectsto the total number of student participants?

There are 30 altogether, 12 are doing plants, 8 are making volcanoes.

12+8=20

30-20=10

10 is the number of students doing other projects.

The ratio of students doing other projects to the TOTAL amount of people is 10/30 to simplify, you divide 10 and you get 1/3