The second number in the given number-pairs is obtained by performing certain mathematical operation(s) on the first number. The same operation(s) is/are followed in all the number-pairs except one. Find that odd number-pair.
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 5 : 685.
The logic followed in the options is shown below:
Logic: First no.2 × (First no. × 2) = Second no.
Option (1) 9 : 1458 → 92 × (9 × 2) = 81 × 8 = 1458
Option (2) 3 : 54 → 32 × (3 × 2) = 9 × 6 = 54
Option (3) 5 : 685 → 52 × (5 × 2) = 25 × 10 = 250 ≠ 685
Option (4) 5 : 250 → 52 × (5 × 2) = 25 × 10 = 250
Thus, 5 : 250 is odd number-pair.
Hence, 5 : 250 is the correct answer.