A cube-shaped tank with an edge length of 20 centimetres contains 3.75 litres of water. The capacity of the tank is 8L. How much more water is needed to fill the tank completely?
The volume of the cube-shaped tank is the cube of the edge length: 20^3 = 8,000 cubic centimeters (or milliliters).
Since 1 liter is equal to 1,000 milliliters, the tank already contains 3.75 x 1,000 = 3,750 milliliters of water.
The remaining capacity of the tank is 8 x 1,000 = 8,000 milliliters.
To fill the tank completely, we need 8,000 - 3,750 = 4,250 milliliters more water.
Therefore, we need 4.25 liters more water to fill the tank completely.
To find out how much more water is needed to fill the tank completely, we need to calculate the difference between the tank's capacity and the current amount of water in it.
First, let's find the volume of the tank. Since it is a cube, the volume can be calculated by multiplying the edge length by itself three times.
Volume of the tank = (Edge length)^3
= (20 cm)^3
= 20 cm × 20 cm × 20 cm
= 8000 cm³
Now, let's convert the volume to liters. Since 1 liter is equal to 1000 cm³, we can divide the volume by 1000 to get the volume in liters.
Volume of the tank in liters = (Volume of the tank in cm³) / 1000
= 8000 cm³ / 1000
= 8 L
We are given that the tank currently contains 3.75 liters of water.
The amount of water needed to fully fill the tank = Capacity of the tank - Current amount of water
= 8 L - 3.75 L
= 4.25 L
Therefore, 4.25 liters of water is needed to fill the tank completely.