<PRE><B>Question 306405</B>
C=2PI*R
4x-10pi 
4X-10PI=2PI*R
(4X-10PI)/2=PI*R
2X-5PI=PI*R
R=(2X-5PI)/PI ANS.
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(5/2)pi 
5PI/2=2PI*R
R=(5PI/2)/2PI
R=(5PI/2)(1/2PI)
R=5PI/4PI
R=5/4 ANS.
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14pi 
14PI=2PI*R
R=14PI/2PI
R=7 ANS.
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(x + y)pi 
(X+Y)PI=2PI*R
R=(X+Y)PI/2PI
R=(X+Y)/2 ANS.
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