Four pairs of numbers have been given, out of which three are alike in some manner, while one is different. Choose out the odd one.
Answer & explanation
Correct answer: option 1
1) 73 - 79,
73 and 79 are consecutive prime.
2) 31 - 41,
There is 01 prime number between them.
3) 61 - 71,
There is 01 prime number between them.
4) 83 - 97,
There is 01 prime number between them.
Thus, 73 - 79 is the odd one.