7B
7A-55% boy, 45% girl
7B-30% boy, 70% girl
0.5*x+0.6*y=0.6(200) where x is quantity of 1st and y is 2nd vinegar.
so, 5x+6y=6(200)=1200
5x+6y=1200......(1)
x+y=200..........(2)
(1)-5*(2)⇒y=1200-1000=200,x=0
so, you just take 200 ml of second vinegar. In fact, this calculation can be skipped coz we were asked the 2nd vinegar directly in the question.
The area of a rectangle is length times width so plug the numbers in to find the width witch would = 3/4
3.2x(8-3)+8:
3.2x(5)+8:
16 +8: 24
