Let S_{n} denote the sum of first n-terms of | vedclass

Name: PDF Generator App | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

$S_{10}=530 \Rightarrow \frac{10}{2}\{2 a+9 d\}=530$

$\Rightarrow 2 a+9 d=106 \ldots .(1)$

$	ext { and } S_{5}=140 \Rightarrow \frac{5}{2}\{2 a

Vedclass · Accepted Answer

$1862$

Vedclass · Answer

$S_{10}=530 \Rightarrow \frac{10}{2}\{2 a+9 d\}=530$

$\Rightarrow 2 a+9 d=106 \ldots .(1)$

$	ext { and } S_{5}=140 \Rightarrow \frac{5}{2}\{2 a+4 d\}=140$

$\Rightarrow 2 a+4 d=56 \ldots . .(2)$

$\Rightarrow 5 d=50 \Rightarrow d=10 \Rightarrow a=8$

Now, $S_{20}-S_{6}=\frac{20}{2}\{2 a+19 d\}-\frac{6}{2}\{2 a+5 d\}$

$=14 a+175 d$

$=(14 	imes 8)+(175 	imes 10)$

$=1862$

Let $S_{n}$ denote the sum of first $n$-terms of an arithmetic progression. If $S_{10}=530, S_{5}=140$, then $\mathrm{S}_{20}-\mathrm{S}_{6}$ is equal to :

Similar Questions

Find the sum of odd integers from $1$ to $2001 .$

If $a_m$ denotes the mth term of an $A.P.$ then $a_m$ =

The number of common terms in the progressions $4,9,14,19, \ldots \ldots$, up to $25^{\text {th }}$ term and $3,6,9,12$, up to $37^{\text {th }}$ term is :

If the sum of $n$ terms of an $A.P.$ is $3 n^{2}+5 n$ and its $m^{\text {th }}$ term is $164,$ find the value of $m$

If all interior angle of quadrilateral are in $A.P.$ If common difference is $10^o$, then find smallest angle ? .............. $^o$