Answer: 15
Explanation:
Given: The present ratio of students to teachers at a certain school is
to
. If the student enrollment were to increase by
students and the number of teachers were to increase by
, the ratio of students to teachers would then be
to
.
To Find: What is the present number of teachers.
Solution:
let the number of teachers in schools are

As the current ratio of students to teachers is
to

Number of students in school are

Now,
If number of student enrollment and teachers were to increase by
and
respectively.
New number of students in school would be

New number of teacher in school would be

new ratio of students to teachers is





Hence the number of teachers in school is
