1, k, 7 , 5k , 31, 7(k^2) is the sequence k = ?

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25 Jul 2011 k ?

1, k, 7 , 5k , 31, 7(k^2) is the sequence
k = ?

OPtion

1) 2
2) 3
3) 4
4) 8
5) 9
6) 12
7) 18
8) 20
9) 25
10) none of these

Solution

the sequence formula is
(2^N) - 1
where N is 1 to 6

so k will be 3

Correct Option: 2 Best Solution (0)