   # Three non-concentric circles of equal radii are drawn such that each circle touches the other two externally...

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Three non-concentric circles of equal radii are drawn such that each circle touches the other two externally. The centres are joined to form a triangle whose area is 17320.5 cm^2. Find the area of the triangle not included in the circles.  posted Oct 30, 2015

5236.6 sq cm. If the radius of each circle is a, the equilateral triangle has base 2a and height 1.73205 a giving the area equal to 1.732.5 a*a and equating this to 17320.5 gives a=100 cm. Since the angles of the triangle are 60 degrees, in each case the area of the triangle not included in the circle is 1/6th the area of the circle of 360 degrees. Each case this comes to one sixth of 3.142*100^2 that is 5236.6 sq cm answer Mar 5, 2017

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