Answer:
The pool that they buy is the circular pool which Marsha wants
The cost of the circular pool is $471.25
Step-by-step 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
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The other terms can't be combined.
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