Advanced Math practice question

Answer: 3

V = πr²h with h = 2r: πr²(2r) = 2πr³ = 54π → r³ = 27 → r = 3.

Common wrong answers

If you answered 6

6 is the height, not the radius.

If you answered 9

9 is r², from solving r² = 9 as if the equation were πr² = 9π.

If you answered 27

27 is r³.

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