Question

A resort is building a scuba diving lagoon in the shape of an upside down pyramid. The top of the lagoon is a rectangle that is 50 feet by 20 feet, and the deepest point of the lagoon is in the middle at 25 feet deep. How much water does the lagoon hold?(1 point)
Responses

25,000 ft.3
25,000 feet cubed

75,000 ft.3
75,000 feet cubed

95 ft.3
95 feet cubed

8,333.33 ft.3

1 answer

To determine the volume of the upside down pyramid-shaped lagoon, we can use the formula for the volume of a pyramid, which is:

\[ V = \frac{1}{3} \times \text{Base Area} \times \text{Height} \]

In this case, the base of the pyramid (the top of the lagoon) is a rectangle measuring 50 feet by 20 feet.

  1. First, calculate the area of the base:

\[ \text{Base Area} = \text{Length} \times \text{Width} = 50 , \text{ft} \times 20 , \text{ft} = 1000 , \text{ft}^2 \]

  1. The height of the pyramid (the depth of the lagoon) is 25 feet.

  2. Now, substitute these values into the volume formula:

\[ V = \frac{1}{3} \times 1000 , \text{ft}^2 \times 25 , \text{ft} \]

\[ V = \frac{1}{3} \times 25000 , \text{ft}^3 \]

\[ V = \frac{25000}{3} , \text{ft}^3 \approx 8333.33 , \text{ft}^3 \]

Thus, the volume of the lagoon is approximately 8333.33 ft³.

So, the correct response is:

8,333.33 ft.³