If the radius of a circle is decreased 50%, what happens to the area?  Answers.
A) 10 % decrease	B) 20 % decrease	C) 75 % decrease	D) 40 % decrease	E) 50 % decrease

Rationale: "area of square = pi * radius ^ 2 new radius = 0.5 * old radius so new area = ( 0.5 ) ^ 2 old area = > 0.25 of old area = > 25 % old area ans : c"
Answer: C