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: A
Explanation
The correct answer is option 1 i.e. 80 : 9.
Logic used : (Second Number)2 - 2 = First number
⇒142 : 12
(12)2 - 2 = 144 -2 = 142
⇒23 : 5
(5)2 - 2 = 25 - 2 = 23
⇒7 : 3
(3)2 - 2 = 9 - 2 = 7
Except for Option 1
⇒80 : 9
(9)2 - 2 = 81 -2 = 79 not equal to 80
Hence, the correct answer is 80 : 9.