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Please please please please help meeee l don’t understand I need help

Please please please please help meeee l don’t understand I need help-example-1
User Tommy Levi
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1 Answer

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14 votes

Answer:

Explanation:

Calculate Circumference = 2π·r and Area = π·r²

1. Given : diameter = 221 mm

d=2·r so because the diameter is twice as big as the radius r = 221/2

Circumference = 2π·r = 2·π·221/2 = 221π ≈ 694.3 mm

Area = π·r² = π·(221/2)² = π·(221²/2²) ≈38,359.6 mm²

2. Given: radius = 2cm

Circumference = 2π·r = 2·π·2 = 4·π ≈ 12.6 cm

Area = π·r²= π·2² = 4π ≈ 12.6 cm²

3 and 4 are similarly solved

Calculate the arc length and area for each sector.

Arc length = 2·π·r· (x/360) and Area of sector = π·r²(x/360)

1. Given: radius = 21 m, and angle of sector x = 133°

Arc length = 2·π·r· (x/360) = 2·π·21· (133/360) ≈ 48.7 m

Area of sector = π·r²(x/360) = π·21²(133/360) ≈ 511.8 m²

2. Given: radius = 3.4 Km , and angle of sector x = 22°

Arc length = 2·π·r· (x/360) = 2·π·3.4· (22/360) ≈ 1.3 Km

Area of sector = π·r²(x/360) = π·3.4²(22/360) ≈ 2.2 Km²

3 and 4 are similarly solved

Please please please please help meeee l don’t understand I need help-example-1
User Emil Aspman
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2.5k points