1.
a-b=8428
a=24326
24326-b=8428
b=24326-8428
b=15898
a+b=?
24326+15898=40224
2.
CISTERNA 1 = 648 l de benzina
CISTERNA 2 = 1/4 x 648 = 162 l de benzina
CISTERNA 3 = 1/2 x 162 = 81 l de benzina
Cisterna 1 + Cisterna 2 + Cisterna 3 = 648+162+81= 891 l in total .