Question
Find:
Which term in the $A.P. 84, 80, 76, ..... is 0?$
Which term in the $A.P. 84, 80, 76, ..... is 0?$
✓
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, $n^{th}$ term of $A.P.$
$a_n = a + (n - 1)d$
$\Rightarrow 0 = 84 + (n - 1) - 4$
$\Rightarrow 0 = 84 + (-4n + 4)$
$\Rightarrow 0 = 84 - 4n + 4$
$\Rightarrow 4n = 88$
$\Rightarrow\ \text{n}=\frac{88}{4}$
$\Rightarrow n = 22$
Hence, $22^{th}$ term of the given A.P. is 0.
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, $n^{th}$ term of $A.P.$
$a_n = a + (n - 1)d$
$\Rightarrow 0 = 84 + (n - 1) - 4$
$\Rightarrow 0 = 84 + (-4n + 4)$
$\Rightarrow 0 = 84 - 4n + 4$
$\Rightarrow 4n = 88$
$\Rightarrow\ \text{n}=\frac{88}{4}$
$\Rightarrow n = 22$
Hence, $22^{th}$ term of the given A.P. is 0.
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