b----g4
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Hi, I'm stuck on a Q from the 2005 UKMT SMC, and am wondering if anyone can help:
A cube fits exactly inside a sphere and another sphere fits exactly inside this cube. What is the ratio of the smaller sphere to the larger sphere?
The answer is (A) - 1:3√3
Could anyone explain why R^2 = r^2 + r^2 + r^2, instead of R^2 = r^2 + r^2 ? (R = radius of big sphere, r = rad of little sphere)
Any help would be greatly appreciated - thanks for reading
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mqb2766
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(Original post by b----g4)
Hi, I'm stuck on a Q from the 2005 UKMT SMC, and am wondering if anyone can help:
A cube fits exactly inside a sphere and another sphere fits exactly inside this cube. What is the ratio of the smaller sphere to the larger sphere?
The answer is (A) - 1:3√3
Could anyone explain why R^2 = r^2 + r^2 + r^2, instead of R^2 = r^2 + r^2 ? (R = radius of big sphere, r = rad of little sphere)
Any help would be greatly appreciated - thanks for reading
Its 3D (pythagoras), not 2D, if thats what youre confused about?
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Cs115
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Sorry for how messy it is lol
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