Question

Find the number of terms of the A.P.
$41,38,35,...,8?$

Answer 1

Here, $a=41,d=38-41=-3$ and $a_n=8$

Where $a_n=a+(n-1)d$

$\Rightarrow 8=41+(n-1)(-3)$

$\Rightarrow 8=41-3n+3$

$\Rightarrow 8=44-3n$

$\Rightarrow 8-44=-3n$

$\Rightarrow -36=-3n$

$\Rightarrow n=\frac{-36}{-3}=12$

Hence, the number of the terms in the given AP is $12$