Question

ANSWER THIS WITH PROPER EXPLANATION AND I'LL MARK YOU THE BRAINLIEST ​

Answer 1

Answer:

49

Step-by-step explanation:

1) We know that the 1 in 1:7:5 will represent the teachers and because when we take a look at the teacher to student ratio its 1:7, this means that there are 8 teachers in total because there are 8 new teachers.

2) Next, we know that the ratio to boys and girls is 7:5 and in general it's 1:7, the one representing the teachers and the 7 representing the total number of students.

3) Because of this what we want to do is multiply 8 x 5 so that we get 40.

4) Then we are going to add 9. The reason for this is be because of the opposites rule. They are leaving so one would think this is subtraction but this is addition.

5) When we add 40 + 9 we get 49. Therefore, this results in the answer being a) 49.

Here's an example of the oppisites rule coming into action:

v2= v1 +t (ad), so if we want to isolate t we would do is have t = v2 - v1/ad. This is because v2 coming over would be negative but opposite rule means that it would be +, then we do negative v1 (subtraction), and we move ad below because in the original it's multiplying so now we do division.

I hope this is helpful for you!