The radius of a sector of a circle is 7 cm. If the measure of the arc of the sector is - three right angles; find the area of the sector in case. - Geometry Mathematics 2

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Sum

The radius of a sector of a circle is 7 cm. If the measure of the arc of the sector is - three right angles; find the area of the sector in case.

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Solution

The radius of the sector of the circle, r = 7 cm

 Measure of arc of the sector = θ = 3 × 90º = 270º

∴  Area of the sector = `"θ"/360` × πr2

∴  Area of the sector =  `270/360 × 22/7 × (7)^2`  

∴  Area of the sector = `3/4 × 22 × 7`

∴  Area of the sector = `3/2 × 11 × 7`

∴  Area of the sector = `231/2`

∴  Area of the sector = 115.5 cm2

  Is there an error in this question or solution?
Chapter 7: Mensuration - Practice set 7.3 [Page 155]

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Balbharati Mathematics 2 Geometry 10th Standard SSC Maharashtra State Board
Chapter 7 Mensuration
Practice set 7.3 | Q 10.3 | Page 155

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