# Aptitude - Odd Man Out and Series - Discussion

Discussion Forum : Odd Man Out and Series - Missing No. (Q.No. 10)
Directions to Solve
Insert the missing number.

10.
7, 26, 63, 124, 215, 342, (....)
481
511
391
421
Explanation:

Numbers are (23 - 1), (33 - 1), (43 - 1), (53 - 1), (63 - 1), (73 - 1) etc.

So, the next number is (83 - 1) = (512 - 1) = 511.

Discussion:
10 comments Page 1 of 1.

Asinei Uganda said:   1 year ago

Ankitchoudhary said:   2 years ago

Himani Prajapati said:   3 years ago
U can also solve by this way.

7+0=7.
2+6=8,
6+3=9,
And it will repeat again so after 342=3+4+2= 9.
Then 511 will be next number bcoz sum of digits is 5+1+1 =7.

Hritik said:   4 years ago

Cube of 0+1=1.
Cube of 1+1=2.
Cube of 2+1=9.

But there is no any cube for 37.
Cube of 4+1=65,
Cube of 5+1=126.
Cube of 6+1=217.

That's why 37 is odd in this group.

Jyoti yadav said:   5 years ago
1 2 9 37 65 126 217 ?

Please solve the given series with the correct explanation.

Jagadeesh Garimella said:   7 years ago
There is one more way but lengthy:

26 - 7 = 19,
63 - 26 = 37,
124 - 63 = 61,
215 - 124 = 91,
342 - 215 = 127:.

If we take the remainders and subtract,
37 - 19 = 18,
61 - 37 = 24,
91 - 61 = 30
127 - 91 = 36 which are multiples of 6, hence the last number should have the difference of 42.

Hence 127 + 42 =169. This should be added to 342 to get the answer.

Princess said:   9 years ago
@Bhupinder Singh.

Your logic is not working here as the sum of digits of option D (421) is 4+2+1=7, than how we can say the answer is B?

Ffd said:   9 years ago
I too in same way and that is also the possible way.