To find out how much more water is needed to fill the fish tank completely, we need to calculate the total volume of the tank and then subtract the amount of water it already contains.

Step 1: Calculate the total volume of the tank in cubic centimeters (cm³).

The dimensions of the tank are:

• Length = 48 cm
• Width = 24 cm
• Height = 30 cm

The volume $V$ of the rectangular tank is given by: $V = \text{Length} \times \text{Width} \times \text{Height}$ $V = 48 \, \text{cm} \times 24 \, \text{cm} \times 30 \, \text{cm}$ $V = 34,560 \, \text{cm}^3$

Step 2: Convert the total volume from cubic centimeters to liters.

Since 1 liter is equal to 1,000 cubic centimeters: $\text{Total Volume in Liters} = \frac{34,560 \, \text{cm}^3}{1,000}$ $\text{Total Volume in Liters} = 34.56 \, \text{L}$

Step 3: Find the amount of water needed to fill the tank.

The tank already contains 6.75 liters of water, so the additional water needed is: $\text{Additional Water Needed} = 34.56 \, \text{L} - 6.75 \, \text{L}$ $\text{Additional Water Needed} = 27.81 \, \text{L}$

Final Answer:

You need 27.81 liters of water to fill the tank completely.

Would you like further details or have any other questions?

---

Here are 5 related questions you might find helpful:

1. How do you calculate the volume of a cylindrical tank?
2. What is the conversion between gallons and liters?
3. How would the calculation change if the tank had a different shape?
4. How much water would overflow if the tank were overfilled?
5. How do you calculate the time required to fill the tank with a specific flow rate?

Tip: When dealing with volumes, always ensure that the units are consistent across all steps of the calculation.