Question
Which term of the $AP$ $3, 8, 13, 18, .....$is $88?$
✓
Answer
In the given $AP,$ we have $a = 3$ and $d = 8 - 3 = 5$
Suppose there are $n$ terms in given $AP,$ then
$T_n= a + (n - 1)d $
$⇒ 3 + (n - 1)5 = 88$
$⇒ 3 + 5n - 5 = 88$
$⇒ 5n = 90 ⇒ \text{n}=\frac{90}{5}=18$
Hence, the $18^{th}$ term of given $AP$ is $88.$
Suppose there are $n$ terms in given $AP,$ then
$T_n= a + (n - 1)d $
$⇒ 3 + (n - 1)5 = 88$
$⇒ 3 + 5n - 5 = 88$
$⇒ 5n = 90 ⇒ \text{n}=\frac{90}{5}=18$
Hence, the $18^{th}$ term of given $AP$ is $88.$
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