Question

Find the 30th term of the A.P. 7, 11, 15, 19,....

Answer 1

Heya!

HERE IS YOYR ANSWER:

a1= 7
a2= 11
d = a2-a1 = 11-7 = 4

We know that,

a30= a+29d

= 5+ 29(4)
= 5+116
=121

So, 30 term of AP= 121

:)

Answer 2

$\boxed{\boxed{\large\mathsf{123}}}$
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$\underline{\Large\mathbf{ Given :}}$

$\mathsf{In \: the \: A.P \: 7, 11, 15, 19}$

$\mathsf{First \: term(a) = 7}$

$\mathsf{Common \: Difference (d)} \\\mathsf{ => a_2 - a_1 = 4 }$

$\underline{\Large\mathbf{To \: Find :}}$

$\mathsf{30^{th} term \: of \: a_{30}}$

$\underline{\underline{\huge\mathfrak{Solution :}}}$

$\underline{\textsf{Using the Formula,}}$

$\boxed{\Large\mathsf{a_n = a + (n-1)d}}$

$\mathsf{=> a_{30} = a + (n-1)d}$

$\underline\text{Putting the Values in the Formula, We get,}$

$\mathsf{=> a_{30} = 7+(30-1)4}$

$\mathsf{=> a_{30} = 7 + (29)4}$

$\mathsf{=> a_{30} = 7 + 116}$

$\boxed{\mathbf{=> a_{30} = 123}}$

Hence, the $\mathsf{30^{th}}$ term of A.P is $\mathsf{123.}$
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