5/7th of 28 students is 20 students because, 28 divided into 7 groups has 4 people in it so with five groups of four gives you 20 students. However, this question is asking for the students that didn’t go so you would take 28 minus the 20 students that are going on the field trip to get 8 student. So all in all there will be 8 students that didn’t go on the field trip.
