Arithmetic Ability
Area

35 / 149

Q.

If the radius of a circle is decreased by 50% , find the percentage decrease in its area.

View Answer

Correct choice: A

Explanation:

let original radius = r and new radius = (50/100) r = r/2 original area = πr2 and new area = π(r/2)2 decrease in area = 3πr2/4*1/πr2 *100 = 75%
35 / 149