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Question
A horse is tied with a 21 m laig rope to the corner of a field which is in the shape of an equilateral triangle. Find the area of the field over which it can graze.
Solution
An equilateral triangle has all angles of 60 degrees
The horse will be able to graze over a sector of a circle of radius 21cm and angle 60, so
Area = `60^circ/360^circ pi "r"^2`
`= 60^circ/360^circ xx 22/7 xx 21 xx 21`
= 231 m2
Horse can graze in 231 m2
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