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July 5th, 2018, 12:18 AM   #1
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[ASK] Two Cones

Azis wants to make two cones using cartons. The surface area of the first cone is twice the second. The side length of the first cone is also twice the second. Determine the ratio of those cones' radius!

s1 = 2s2
L1 = 2L2
πr1(r1 + s1) = 2πr2(r2 + s2)
r1(r1 + 2s2) = 2r2(r2 + s2)

I was stuck with quadratic equations...
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July 5th, 2018, 02:41 AM   #2
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Thanks to Denis McField who keeps calling me "Mr. Fly" ...
Are you related to Rufus T. Firefly?
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July 5th, 2018, 05:48 PM   #3
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Are you related to Rufus T. Firefly?
I prefer D. Waterfly, though.
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July 5th, 2018, 10:59 PM   #4
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I was stuck with quadratic equations...
It would seem that the surface area is intended to exclude the area of the base.
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July 5th, 2018, 11:04 PM   #5
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It would seem that the surface area is intended to exclude the area of the base.
But in my language it said "luas permukaan", and it strictly include the base area. Otherwise they would use the phrase "luas selimut" (side area) instead.
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July 6th, 2018, 01:15 AM   #6
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According to Google's translator, "luas permukaan" means "surface area" (as distinct from "total surface area"). Although a more specific phrase is available, it's possible that the need for it was overlooked.
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