Question 118206
How many mm2 are in 3cm2. 
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1cm = 10mm
(1cm)^2 = 100mm^2
3cm^2 = 3(100mm^2) = 300mm^2
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What is the ratio of cm2 to mm2 ?
1cm^2 = 100mm^2
Ratio is 1/100 or 1:100
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Cheers,
Stan H.