If the sum of the first n terms of the series
then n eqals :
18
15
13
29
As we learnt in
Sum of n terms of an AP -
and
Sum of n terms of an AP
- wherein
first term
common difference
number of terms
Option 1)
18
Incorrect option
Option 2)
15
Correct option
Option 3)
13
Incorrect option
Option 4)
29
Incorrect option
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