Surface area % increase (problem solving Q)

Might be an easy question but i cant get it right. Answer is C btw

from cm to mm is 1x10-3. However since we know it is volume: there are 3 dimensions: it will become 1x10-9. Since the ratio would be 1 : 9 you can say the rate increase by 9x : which is other words is 900%. This is a shorter technique that I did when I found a similar question so if anyone else has a more detailed calculation, let me know! :))


I found the answer by dividing the volume of the large cube (1000mm3) by the volume of smaller cube (1mm3) = 1000 small cubes from large one.

Then find the surface area of large cube = 6 * 100mm2 = 600mm2
Small cubes combined = 1000 * 6 * 1 = 6000mm2

% change = (area final - area initial) * 100 / area initial = 900%.


Got it now, thank you!!

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