10th term of below series is: -1, 7, 5, 21, 19, 43, 41, .....

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09 Mar 2017 Series

10th term of below series is:
-1, 7, 5, 21, 19, 43, 41, .....

OPtion

1) 67
2) 69
3) 71
4) 73
5) 75
6) 77
7) 101
8) 110
9) 121
10)None of these

Solution

1^2 - 2 = -1
2^2 + 3 = 7
3^2 - 4 = 5
4^2 + 5 = 21
5^2 - 6 = 19
6^2 + 7 = 43
7^2 - 8 = 41
8^2 + 9 = 73
9^2 - 10 = 71
10^2 + 11 = 111

Correct Option: 10 Best Solution (0)