Question 771243
Let r = radius uf the center hole


r^2(pi) = 0.0136(r+53)^2 (pi)

r^2 = 0.0136(r+53)^2

(r/(r+53))^2 = 0.0136

r/(r+53) = 0.116619

r = (r+53)0.116619

0.883381r =  6.180809

r = 6.996765  

(Rounding it r = 7)

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