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and solve for k. I hope this helps,
Hi Elizabeth. My instinctive response to "scale" questions is this: as linear measurements scale linearly, areas scale quadraticly and volumes scale cubicly. You multiplied the volume by 2.5. (When you "increase by one and a half times" you have the original 1 + the increase of 1.5 = 2.5 times the original size. If you meant to say you increase it by half, then you'd be multiplying the volume by 1.5 instead of 2.5.) That means the cube root of 2.5 is the factor by which you multiply the linear dimensions. The cube root of 2.5 is about 1.3572. Thus the big cup would have a bottom radius of 2.8cm(1.3572), a top radius of (4.9)(1.3572) and a height of 10(1.3572). Cheers,  


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