1. A rectangular fish tank with a square circumference of 160 cm at the bottom. Now pour 18 liter of water into the tank. How high is the water in the tank?

160÷4=40 (cm) =4 (decimeter)

18 ÷ (4× 4) =1.125 (decimeter) = 1 1.25 (cm)

2. The side length of the cubic water tank is 4 decimeters. Pour the water into a cubic water tank with a length of 8 decimeters and a width of 2.5 decimeters. How many decimetres is the water depth?

4×4×4(8×2.5)= 3.2 (decimeter)