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Question
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Solution
Radius of the circle, r = 7 cm
m(arc MBN) = ∠MON = θ = 60º
Area of Sector `= theta/360^\circ xx pir^2`
`60/360 xx pixx7^2`
`1/6 xx pixx49`
`=(49pi)/6 cm^2`
`(49xx22)/(6xx7)`
`1078/42`
≈ 25.67 cm2
Since angle ∠MON = 60∘ and OM = ON = radius = 7 cm
`Area = 1/2 r^2 sin(theta)`
`1/2 xx 7xx7xxsin(60^\circ)`
`=49/2xxsqrt3/2`
`=(49sqrt3)/4`
`= (49xx1.732)/4`
`=84.868/4`
≈ 21.22 cm2
= Area of Sector OMN − Area of Triangle OMN
= 25.67 − 21.22
= 4.45 cm2
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