9514 1404 393
Answer:
$28.14
Step-by-step explanation:
The area of a container will be the sum of the base area and the lateral area. The relevant formulas are ...
A = πr^2 . . . . . . . . area of the circular base with radius r
A = 2πrh . . . . . . . area of the side of the container
The sum of the two areas is ...
Atot = πr^2 +2πrh = πr(r +2h) = π(7/2 cm)(7/2 cm +2·21 cm) = (π/4)(7)(91) cm^2
Atot = 159.25π cm^2 = 0.015925π m^2 . . . . metal area per container
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Then 125 containers will have an area of ...
Aall = (125)(0.015925π m^2) = 1.990625π m^2 ≈ 6.25373 m^2
The price of this amount of sheet metal will be ...
(6.25373 m^2)($4.50 /m^2) = $28.14 . . . cost of 125 containers
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Additional comment
1 cm = 0.01 m, so (1 cm)^2 = (0.01 m)^2 = 0.0001 m^2
