On increasing the diameter of a circle by 40%, its area will be increased by

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KollegeApply · Accepted Answer

96% Let d be the original diameter. Radius ="d"/2 Thus, we have; Original area = $\pi$ xx ("d"/2) = (pi"a"^2)/4 New diameter = 140% of d = ($\frac{140}{100}$xx"d") = (7"d")/5 Now, New radius =(7"d")/5xx2 =(7"d")/10 New area = pixx((7"d")/10)^2 =(49$\pi$"a""^2)/10 Increase in the area`=((49pi"a"^2)/10 - (pi"a"^2)/4)` =(24$\pi$"a"^2)/100 =(6pi"a"^2)/25 ` We have ; Increase in the area`=((6pi"a"^2)/25xx4/(pi"a"^2)xx100)%` = 96 %

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