Three of the following four number pairs are alike in a certain way and thus form a group. Which is the one that does NOT belong to that group?
(NOTE: Operations should be performed on the whole numbers, without breaking down the numbers into their constituent digits. E.g. 13 – Operations on 13 such as adding/subtracting/multiplying etc. to 13 can be performed. Breaking down 13 into 1 and 3 and then performing mathematical operations on 1 and 3 is not allowed.)
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 8-72.
Logic: X-Y → X × (X + 2) = Y
Except for 8-72, all options follow the above-mentioned logic.