I need help with part C of question 18.
With parts A and B, it is best to simplify them down so in this case, the number on the right can be the smallest it can be. A: 30:1. B: 16:1. The reason I've told you this is that now we can see more clearly how many need to be moved to make it equal. 30-16 = 14 is the difference in numbers. To find the middle ground, divide 14/2 (=7) and move that number of student over from A to B. Now, both ratios are 23:1 (30-7=23, 16+7=23), and we know our answer is right. Answer: Move 7 students from School A to School B.
Just take 480+192=672 total students now divide in half 672/2=336 now subtract 192 =144 students needed