If one tank has an 80 x 80cm cross section; the other has a 60 x 60cm cross section. if I pour 100 litres of oil into the larger tank, by how much will the level of the oil in the smaller tank rise?
assuming the tanks are connected at their bases, the oil will equalize when the depth is the same in both tanks.
80*80*h1 = 60*60*h2
h2/h1 = 64/36 = 16/9
9 cm in the larger tank equals 6400*9cm^3 = 57.6 liters
16 cm in the smaller tank holds 3600*16cm^3 = 57.6 liters
scale those depths by 100/115.2 to get the final depths.