Question 695364
what happens to the circumference of a circle if you double the radius? 
Circum = 2(pi)r
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If you double r you get 2(pi)(2r) = 2[2(pi)r] ; you double the Circumference
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and what happens if you double the diameter? 
Circum (pi)d = (pi)(2r)
--If you double d you get (pi)(2d) = 2(pi)d
So, if you double d, you double the Circumference.
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and what happens if you triple the radius?
You get: C = 2(pi)(3r) = 3[2(pi)r]
So, if you triple r, you triple the circumference.
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Cheers,
Stan H.
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