Question

A field is in shape of equilateral triangle in which the length of each side is 70m.A cow is tethered at one of its vertices by a 5m long rope.Find the area of the region in which cow can graze

Answer 1

Given , a cow is tethered with a rope at one vertices of the equilateral triangular field
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Note1 : here is given that cow is tethered only 1 vertices of equilateral triangle . so then you only have to find the area of that particular sector where cow is tethered with rope.
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here,we have given length of rope = 5 m
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Note 2 : length of rope = diameter of sector and diameter of sector = radius of circle
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so now , radius(r) = 5 m
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note 3: area of the field in which the cow can graze = area of sector at vertices B.
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since , the cow is tethered at one vertices of equilateral triangular field and we know that each sides of an equilateral triangle are equal and measure of its each angles = 60°

then ,Find the area of the field in which the cow can graze:
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Required area = 60°/ 360° πr^2

= 60 / 360 × 22 / 7 × (5)^2

= 1 × 22 × 25 / 6 × 7

= 550 /42 =13.09 m^2(approx.)

therefore , the required area in which cow can graze = 13.09 m^2
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Your Answer : Area = 13.09 m^2
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