# 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, (....)

Answer: Option

Explanation:

Numbers are (2^{3} - 1), (3^{3} - 1), (4^{3} - 1), (5^{3} - 1), (6^{3} - 1), (7^{3} - 1) etc.

So, the next number is (8^{3} - 1) = (512 - 1) = 511.

Discussion:

10 comments Page 1 of 1.
Asinei Uganda said:
1 year ago

Thanks for you answer @Jagadeesh.

Ankitchoudhary said:
2 years ago

Agree, Thanks @Jagadeesh Garimella.

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.

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

@Jyoti Yadav.

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.

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.

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.

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?

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.

Venki said:
1 decade ago

No. Because here only one answer has taken. Logic is ok. But apply every time.

Bhupinder Singh said:
1 decade ago

I have soved it in a different way like:

7, 2+6=8, 6+3=9, 1+2+4=7, 2+1+5=8, 3+4+2=9, (4+2+1=7 or 5+1+1=7)

so the series is 7,8,9,7,8,9,7 ....

Please reply me can we apply this logic here or not

7, 2+6=8, 6+3=9, 1+2+4=7, 2+1+5=8, 3+4+2=9, (4+2+1=7 or 5+1+1=7)

so the series is 7,8,9,7,8,9,7 ....

Please reply me can we apply this logic here or not

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