In an A.P. $2+5+8+11+... $, if last term is $95$, then find the number of terms of the series.
Given: In an A.P. $2+5+8+11+... $, if last term is $95$.
To do: To find the number of terms of the series.
Solution:
Here,
First term $a=2$, Common difference $d=3$, Last term $l=95$
As known, $l=a+(n−1)d$
$\Rightarrow 2+(n−1)\times3=95$
$\Rightarrow n=32$
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