Which number is the odd one out: 8, 9, 27, 64?

8Correct answerYour answer9Correct answerYour answer27Correct answerYour answer64Correct answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer B

Correct answer: B

$8 = 2^3$ , $27 = 3^3$ and $64 = 4^3$ are perfect cubes.
9 is $3^2$ , a square but not a cube, so it is the odd one out.

Worth noting

64 is also a perfect square $(8^2)$ , so 'square' does not single out one number here (9 and 64 are both squares). Only 'cube' splits the four as three and one.

Concept: Odd one out: perfect cubes
Typical timeTypical: 70 s
Your timeYours: —

The rule this testsClassification: the odd one out

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Which number is the odd one out: 8, 9, 27, 64?

Explanation