Question

If the radius of a circle is increased by. 10% then corresponding increase in the area off the circle is ............%
$\pi = 3.14$

Answer 1

radius 10%= 1/10----10(initial radius)====11(new radius)                                    
Area=pi*r^2
Ini.Area=100*pi
New Area=121*pi
Increase in area= 21/100 *100 =21%