Three of the following numbers are alike in a certain way and one is different. Pick the odd one out.
(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 /deleting /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: D
Explanation
The correct answer is option 4 i.e. 21 – 14 – 72.
1) 15 – 3 – 108 → (15 - 3) × 9 = 12 × 9 = 108
2) 18 – 11 – 63 → (18 - 11) × 9 = 7 × 9 = 63
3) 12 – 8 – 36 → (12 - 8) × 9 = 4 × 9 = 36
4) 21 – 14 – 72 → (21 - 14) × 9 = 7 × 9 = 63 ≠ 72