Answer:
30 students liked both soccer and football
Step-by-step explanation:
Sets Operations
Set are collections of elements with something in common or grouped in some way. Sets S and F can be totally independent if they have no elements in common or can have some elements common to both that form the so-called Intersection of sets S and F.
We know a total of 350 students were asked about their preference for soccer or football. We also know 200 said they liked soccer and 180 liked football. Since the sum of both sets is greater than the total of students, it's sure a group of students that like both soccer and football. It can be easily computed that 200+180-350 = 30 students are in the intersection of both sets, thus the answer is 30.