Find the odd number pair: 5 : 26, 6 : 37, 7 : 49, 8 : 65.

A5 : 26

B6 : 37

C7 : 49 ✓ Correct

D8 : 65

Correct answer: (C) 7 : 49

Explanation

7 : 49 is the odd pair.

5 : 26, 6 : 37 and 8 : 65 follow n : n^2 + 1 (5^2+1 = 26, 6^2+1 = 37, 8^2+1 = 65).

In each the second number is the first squared plus 1.

7^2 + 1 = 50, but the pair shows 49, not 50.

So the pair breaking n : n^2 + 1 stands apart.

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