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Question
Find the area of sector whose central angle and radius are 60o and 21 cm respectively.
`(pi = 22/7)`
Solution
Area =`theta/360 xx pi"r"^2`
⇒ A `= 60/360 xx 22/7 xx 21^2`
⇒ A` = 1/6 xx 22/7 xx 21 xx 21`
⇒ A = 11 × 21
⇒ A = 231 cm2
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