Find the odd number: 25, 27, 125, 343.

A25 ✓ Correct

B27

C125

D343

Correct answer: (A) 25

Explanation

25 is the odd number.

27 = 3 x 3 x 3, 125 = 5 x 5 x 5 and 343 = 7 x 7 x 7 are perfect cubes.

Each of these three is a whole number cubed.

25 = 5 x 5 is a perfect square, not a cube.

So the non-cube stands apart.

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