Last year Gill’s cylindrical 21st birthday cake wasn’t big enough to feed all her friends. This year she will double the radius and triple the height.
What will be the ratio of the volume of this year’s birthday cake to the volume of last year’s cake? Leave your ratio in its simplest form.
Select one option, then click Submit.
12:1
7:1
6:1
4:1
3:1
Select an option, then submit.
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Intermediate Mathematical Challenge 2010 (2010)
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