Friday

July 25, 2014

July 25, 2014

Posted by **sarah** on Friday, June 28, 2013 at 10:58am.

Area (to the nearest square centimeter) = cm2

I plugged in everything C = 2 r

C=2x3.14x100= 628 <<< The computer said it was WRONG !

Then, I tried C= 2X3.14X50= 314 !!!

If I am wrong can you EXPLAIN to me what I am doing wrong.

- Math -
**Steve**, Friday, June 28, 2013 at 11:03amC = 2πr

r = C/2π

area = πr^2 = π(C/2π)^2 = C^2/4π

so, area = 10000/4π = 2500/π = 796 cm^2

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