Maximum value of sum of arithmetic progression 50, 48, 46, 44 ........ is :-

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8. Sequences and Series

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Maximum value of sum of arithmetic progression $50, 48, 46, 44 ........$ is :-

A

$325$

B

$648$

C

$652$

D

$650$

Solution

For maximum sum $\Rightarrow \mathrm{T}_{\mathrm{n}}=0$

$a+(n-1) d=0$

$\Rightarrow 50+(n-1)(-2)=0 \Rightarrow n=26$

So $S_{26}=\frac{26}{2}[2 \times 50+25 \times(-2)]=650$

Standard 11

Mathematics

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