The answer is 25 . I hope this helped.
Her error was that she misplaced the numbers
-30x ≥ -300
its supose
to be -30x ≥ 200
Well, ratios are basically fractions. There are 12 boys, so the ratio is 12/25. Since 25 - 12 is 13, there are thirteen girls, so the ratio of girls to student is 13/25.
j = bH
Switch sides
bH = j
Divide both sides by H
bH/H = j/H
Simplify
b = j/H
Therefore b = j/H
I hope this is what you are looking for.