The ratio of boys to girls at north middle school is 3 boys to every 4 girls. if the seventh grade has 120 girls, how many total students are in the seventh grade?

There are 210 students in 7th grade. 90+120=210. You have to cross multiply by setting up two proportions (3/4 and x/120) and multiply 3 by 120 and multiply 4 by x. That leaves you with 360 on one side and 4x on the other. In order to find the value of x you have to isolate it by dividing both sides by 4 to get rid of the 4 on the side that has x. And you do 360/4=90. Then just add the amount of boys with the amount of girls to get your total.

1.3

step-by-step explanation:

3x2=6   9x+6

bring down the 6 on both sides

6+6=12

12= 9x

divide by 9

12/9 =

1.3 =x

jml angle lkj & angle mj = lm