Final answer:
The relationships between the number of seventh graders and eighth graders who play sports are not proportional.
Step-by-step explanation:
To determine if the relationships are proportional between the number of seventh graders and eighth graders who play sports, we need to set up a ratio and compare them.
For seventh graders, the ratio of students who play sports to total students is 25 to 75.
For eighth graders, the ratio is 30 to 120.
These can be simplified to 1 to 3 and 1 to 4, respectively.
Since these two simplified ratios are not equal, we can conclude that the relationships are not proportional.