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प्रश्न
In a circle of radius 10 cm, an arc subtends an angle of 108° at the centre. what is the area of the sector in terms of π?
उत्तर
We have given the radius of the circle and angle subtended at the centre of the circle.
`r=10 cm`
`θ=108°`
Now we will find the area of the sector.
Area of the sector=`θ/360 xxpir^2`
Substituting the values we get,
Area of the sector=` 108/360xxpixx10^2` ...........(1)
Now we will simplify the equation (1) as below,
Area of the sector =`3/10xxpixx100`
Area of the sector =`3xxpixx10`
⇒ Area of the sector =`30 pi`
Therefore, area of the sector is`30 picm^2`
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