If the height of a cone does not change and the radius of its bottom increases by one third, how much does the volume increase? Don't be wrong,
Bottom radius increased by 1 / 3
The base area increases by (1 + 1 / 3) × (1 + 1 / 3) - 1 = 7 / 9
If the height remains unchanged, the volume increases by 7 / 9
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