Final answer:
To find the number of students who attended the game, divide the total number of students by 3.
Step-by-step explanation:
To find the number of students who attended the game, we need to calculate one-third of the total number of students. In this case, there are 270 students in the school, so we divide 270 by 3 to find one-third: 270 / 3 = 90 students. Therefore, 90 students attended the football game.