# Aptitude - Odd Man Out and Series - Discussion

Discussion Forum : Odd Man Out and Series - Find Wrong No. (Q.No. 11)
Directions to Solve
Find out the wrong number in the series.

11.
64, 71, 80, 91, 104, 119, 135, 155
71
80
104
119
135
Explanation:

Go on adding 7, 9, 11, 13, 15, 17, 19 respectively to obtain the next number.

So, 135 is wrong.

Discussion:
12 comments Page 1 of 2.

ALDO JENO DHASS said:   3 months ago

Devil said:   5 years ago
71 should be the answer as it is the only prime no in the series.

Kunal Shriwas said:   6 years ago
But 71 is the only Prime number in the series so it should be correct.

Sanky said:   6 years ago
I can't understand this logic. Please explain the logic.

Manish said:   8 years ago
The difference between 1st two number is 7 now add 2 in the difference of 1st 2 no. You will get the difference but 2nd and 3rd. Similarly, adds 2 in this difference you will get different between 3rd and 4th. Check in this way you will find that 135 is wrong instead of this there should be 136.

Pramod g said:   8 years ago
I can't understand this solution please explain it clearly.

Bindu chauhan said:   9 years ago
I can't understand this solution please explain.

Manikant Thakur said:   9 years ago
But we can also think in this way that all no is composite no. other than 71 (Prime No).

So 71 should also be the right answer.