If the diameter of circle R is 50% of the diameter of circle S, the area of circle R is what percent of the area of circle S?  Choose the correct choice from the following options
A) 35%  B) 25%  C) 20%  D) 15%  E) 10%
Let diameter of circle R , dr = 50   and diameter of circle S , ds = 100   Radius of circle R , Rr = 25   Radius of circle S , Rs = 50   Area of circle R/ Area of circle S = (pi * Rr ^2 ) /( pi * Rs^2 )   = (25/50)^2 = (5/10)^2   =25%   Answer :25%
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If the diameter of circle R is 50% of the diameter of circle S, the area of circle R is what percent of the area of circle S?