Answer:
Summer for 9th Graders: 0.14
Fall for 10th Graders: 0.15
Spring overall total: 0.36
Summer overall total: 0.22
Fall overall total: 0.33
Winter overall total: 0.09
Explanation:
Relative frequencies are related to percentages so you can find the answer through that given the total from each grade.
However, adding or subtracting makes the process easier (in my opinion) to find the relative frequency