Answer:
60
Step-by-step explanation:
There are 2+5 = 7 ratio units of students. If we multiply the numbers by 5, we can have a total of 35 ratio units of students: 10 : 25.
Now, we can substitute this into the ratio of teachers to students:
teachers : students = 3 : 35
teachers : (male students : female students) = 3 : (10 : 25)
Then the number of teachers is seen to be 3/25 of the number of female students:
(3/25)(500) = 60 . . . teachers