Find the odd number pair: 343 : 7, 243 : 9, 512 : 8, 216 : 6.

A343 : 7

B243 : 9 ✓ Correct

C512 : 8

D216 : 6

Correct answer: (B) 243 : 9

Explanation

243 : 9 is the odd pair.

343 : 7, 512 : 8 and 216 : 6 follow (cube) : its cube root (7^3 = 343, 8^3 = 512, 6^3 = 216).

In each the first number is the cube of the second.

9^3 = 729, not 243, so 243 : 9 does not fit.

So the pair without the cube link stands apart.

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