The venn diagram above shows a class of 40 students with the games they play. How many of the students play two games only?

To find the number of students who play two games only, we need to add up the number of students in the regions of the Venn diagram that represent playing two games only. Looking at the diagram, we can see that there are two regions that represent playing two games only: the intersection of the football and basketball circles, and the intersection of the basketball and volleyball circles. The number of students who play two games only is the sum of the number of students in these two regions. From the diagram, we can see that there are 7 students in the football and basketball region, and 8 students in the basketball and volleyball region. Therefore, the total number of students who play two games only is: 7 + 8 = 15 So, 15 of the 40 students play two games only.