Fine the sixth term of the series: 1, 6, 21, 60, ...

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18 Jan 2019 Series

Fine the sixth term of the series:
1, 6, 21, 60, ...

OPtion

1) 155
2) 150
3) 165
4) 175
5) 145
6) 215
7) 230
8) 315
9) 135
10) None of these

Solution

nth term of Series is = n*(2^n - 1)
1st term = 1*(2^1 -1 ) = 1
4th term = 4*(2^4 -1 ) = 60
6th term = 6*(2^6 - 1 ) = 378

Correct Option: 10 Best Solution (0)