Question

Question 2, 7 ,28 , 63, 126, ?
Options:-
i 245
ii 215
iii 296
iv 276

Answer 1

Here, we use (n^3 + 1), (n^3 - 1), (n^3 + 1), ...

1^3 + 1 = 1 + 1 = 2,

2^3 - 1 = 8 - 1 = 7,

3^3 + 1 = 27 + 1 = 28,

4^3 - 1 = 64 - 1 = 63,

5^3 + 1 = 125 + 1 = 126,

6^3 - 1 = 216 - 1 = 215.

So, the next number is 215

HOPE THIS MAY HELP U ^-^

Answer 2

Given Series is 2,7,28,63,126.

= > (-1)^2 + 1^3 = 2

= > (-1)^3 + 2^3 = 7

= > (-1)^4 + 3^3 = 28

= > (-1)^5 + 4^3 = 63

= > (-1)^6 + 5^3 = 126

= > (-1)^7 + 6^3 = 215.

Therefore, the next number is 215 - Option(ii).

Hope it helps!