Final answer:
The volume of the fish tank is 600 cubic inches. To fill 90% of the tank, 90% of the volume, which is 540 cubic inches, is needed. Therefore, option A is the correct answer.
Step-by-step explanation:
To find the total amount of water needed to fill 90% of the fish tank, first we calculate the volume of the tank and then take 90% of that volume. The formula for the volume V of a right rectangular prism is V = length × width × height. Using the given dimensions:
- Length (l) = 12.5 inches
- Width (w) = 6 inches
- Height (h) = 8 inches
The volume of the tank is:
V = l × w × h = 12.5 × 6 × 8 = 600 cubic inches
Now, calculate 90% of the total volume:
90% of 600 cubic inches = 0.9 × 600 = 540 cubic inches. Therefore, the total amount of water needed to fill 90% of the fish tank is 540 cubic inches, which corresponds to option A.