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主题：[The Official SAT Question of the Day™] January 21st Wednesday

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A right circular cylinder has height 6 and volume 54

. What is the circumference of its base?
A. 2

B. 3

C. 6

D. 9

E. 18

SAT题目：http://apps.collegeboard.com/qotd/question.do

楼主 Date: 2009-01-21 14:01:05

jasontomonaga

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Hint : The volume of a cylinder with radius r and height h is equal to

r2h. From this formula, you can find the radius and then the circumference of the base of the cylinder.

沙发 Date: 2009-01-21 14:02:05

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Correct Answer: C

Here's Why: The volume of a cylinder with radius r and height h is equal to r2h. Therefore, r2(6) = 54 and r2 = 9, so the radius of the cylinder is 3. The circumference of a circle with radius r is equal to 2r; therefore, the circumference of the base is equal to 6.
Difficulty: Hard
Question Type: Standard Multiple Choice
(Mathematics)

板凳 Date: 2009-01-21 14:02:27

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