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Pete and Marsha are going to buy a swimming pool. Mike wants a rectangular one that is 18 feet wide, 20 feet long, and 6 feet deep, and Marsha wants a circle shaped pool that is 20 feet across and 6 feet deep. They decide to buy the pool that cost less to fill. If the price of water is 25 cents per cubic foot, which pool do they buy and how much does it cost?

User Peter Elliott
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1 Answer

23 votes
23 votes

Answer:

The pool that they buy is the circular pool which Marsha wants

The cost of the circular pool is $471.25

Explanation:

The parameters of the swimming pools which each of Pete and Marsha wants to buy is given as follows;

The dimensions of the pool Pete wants = 18 feet wide, 20 feet long and 6 feet deep

The dimensions of the circle shaped pool Marsha wants = 20 feet across and 6 feet deep

The price of water, P = 25 cents per cubic foot

The pool they decide to buy = The pool that costs less to fill

The volume of water to fill the pool Pete wants, V₁ = 18 ft. × 20 ft. × 6 ft. = 2,160 ft.³

The cost of filling the pool Pete wants, C₁ = V₁ × P

∴ C₁ = 2,160 ft.³ × 25cents/ft.³ = 54,000 cents = 540 Dollars

The volume of water to fill the pool Marsha wants, V₂ = π·(20 ft.)²/4 × 6 ft. ≈ 1,884.96 ft.³

The cost of filling the pool Marsha wants, C₁ = V₁ × P

∴ C₁ ≈ 1,884.96 ft.³ × 25 cents/ft.³ ≈ 47,124 cents = 471.24 Dollars

The pool that they buy is the circular pool that Marsha wants and it costs $471.24 to fill

User Dturvene
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