Question

Qual a soma dos 5 termos de uma p.a em que o primeiro termo e 6 e o ultimo e 40

Answer 1

Boa tarde!

Dados;

A1 → 6

An → 40

N → 5

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$\textup{Sn}=\frac{(\textup{a1+an).n}}{2}$

$\textup{S5}=\frac{(\textup{6+40).5}}{2}$

$\textup{S5}=\frac{\textup{46.5}}{2}$

$\textup{S5}=\frac{\textup{230}}{2}$

$\textup{S5}=\boxed{\boxed{115}}$

Att;Guilherme Lima