The present ratio of students to teachers at a certain school is 30 to 1. if the student enrollment were to increase by 50 students and the number of teachers were to increase by 5, the ratio of students to teachers would then be 25 to 1.
what is the present number of teachers?

15

Step-by-step 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

the answer should be a. snail

answer: - (a)

(b) 88 seats

step-by-step explanation:

given: in an auditorium, there are 22 seats in the first row and 28 seats in the second row.

thus first term=

second term=

the number of seats in a row continues to increase by 6 with each additional row.

⇒d= 6

a) given formula :

b)   let the number of seats (n) = 12

substitute n=12 in the explicit rule formed in (a)

∴there are 88 seats in 12 rows.