A rectangular fish tank has a base area of 0.3 m squared and height 30 cm and is filled with 80 L of water. Ten large fish with volume 50 cm cubed each are placed into the tank. By how much does the water rise?

Answer 1

each 1cm layer of water has a volume of 30^2 * 1 = 900 cm^3

So, what's the total volume of the fish? Divide that by 900cm^3 to find how much the water level rises.