Q17 of 68 Page 16

The radii of two circles are 19cm and 9cm respectively. Find the radius and area of the circle which has its circumference equal to the sum of the circumferences of the two circles..

Radius of the first circle = 19cm


Circumference of first circle = 2πr


= 2π × 19cm


Radius of second circle = 2πr


=2π × 9cm


Total circumference = 2π × 19 + 2π × 9


= 2π (19+9)



2πr = 176



Area of circle =


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