Which term of the A.P. 3, 14, 25, 36.... is 121 more than its 82th term ?

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13 Oct 2010 A.P series

Which term of the A.P. 3, 14, 25, 36.... is 121 more than its 82th term ?

OPtion

1) 110
2) 89
3) 83
4) 93
5) 62
6) 86
7) 94
8) 91
9) 99
10) 103

Solution

Here a = 3 , d = 11
So t(54) = 3 + (82 —1).11 = 894
Let n be number of terms
So t(n) = 894 + 121 = 1015
=> 3 + ( n—1).11 = 1015
=> n = 93

OR

121/11 = 11
so that term would be
82+11 = 93

Correct Option: 4 Best Solution (7)