Question 419128
$1.5 ----x
$2.25-----2x
$4.5------300-3x

...
1.5*x+2.25*2x+4.5*(300-3x)=300*3
6x-13.50x+1350=900
-7.5x=-450
/-7.5
x=60 liters------- $1.5
120liters----------$2.25
120liters----------$4.50