Q11 of 36 Page 253

Select a proper option (a), (b), (c) or (d) from given options and write in the box given on the right so that the statement becomes correct:

If the radius of a circle is increased by 10 %, then corresponding increase in the area of the circle is ………. (π = 3.14)


r be the radius of the circle


Area of the circle = πr2


10% increase in radius = 1.1r


Area of circle with new radius = π(1.1r)2


= 1.21πr2


increase in area = 1.21πr2 - πr2


= 0.21 πr2


∴ 21% increase in the area of circle


So, option(c) is the correct answer.

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