The second number in the given number-pairs is obtained by performing certain mathematical operation(s) on the first number. The same operation(s) are followed in all the number-pairs EXCEPT one. Find that odd number-pair.
Answer & explanation
Correct answer: option 4
THE LOGIC;
1) 4 : 48,
\( {4}^{3} \) - \( {4}^{2} \) = 48
64-16 = 48
2) 6 : 180,
\( {6}^{3} \) - \( {6}^{2} \) = 180
216-36 = 180
3) 8 : 448,
\( {8}^{3} \) - \( {8}^{2} \) = 448
512-64 = 448
4) 9 : 639,
\( {9}^{3} \) - \( {9}^{2} \) = 639
729-81 = 648 not 639
Thus, 9 : 639 is the odd one.