62 is the awnser for this
Answer: 20 students participate in school sports.
Step-by-step explanation:
Since, Mrs. Perez has 28 students.
And, According to the question, 5 /7 of those students participate in school sports.
Therefore, the students participate in school sports = 5/7 of the total number of the students
= 
= 20
Thus 20 students participate in school sports.