Find: Which term in the A.P. 84,80,76, .. is 0 ? - Vidyadip

Question

Find:
Which term in the A.P. $84,80,76, \ldots .$. is $0$ ?

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Answer

In the given problem, we are given an A.P. and the value of one of its term. We need to find which term it is $( n )$.
So here we will find the value of $n$ using the formula, $a_n=a+(n-1) d$.
Given,
A.P., $84, 80, 76, .....$
$a_n=0$
Here,
First term $= 84$
Difference $=(80-84)=-4$
We have to find which term of A.P. is $0$
We know, $n ^{\text {th }}$ term of A.P.
$a_n=a+(n-1) d$
$\Rightarrow 0=84+(n-1)-4$
$\Rightarrow 0=84+(-4 n+4)$
$\Rightarrow 0=84-4 n+4$
$\Rightarrow 4 n=88$
$\Rightarrow n=\frac{88}{4}$
$\Rightarrow n=22$
Hence, $22^{\text {th }}$ term of the given A.P. is $0$ .

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