# Mathematics

A sector of a circle of radius 7cm subtends angle 270° at the centre. Calculate a. Length of arc b. Area of sector c. Perimeter of sector

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1. easy way: 270° is 3/4 of a circle, so the
arc is 3/4 * 2πr
area is 3/4 * πr^2

But, using the same logic, you have 270/360 * 2π = 3π/2, so
arc is rθ = 3 * 3π/2
area is 1/2 r^2 θ = 1/2 * 9 * 3π/2
perimeter = arc + 2 radii = 9π/4 + 2*3

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oobleck

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3. BODMAS operation is allow in any equation try and use "bodmas" to solve equation. math is the simple work in life and everything in life contain caculation

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5. I don't get the answer

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