Question

qual é a soma dos termos da P.A.

(25,45,65,85,105,125,145,) ?​

Answer 1

$\mathsf{S_{7}=\dfrac{7(25+145)}{2}}$

$\mathsf{S_{7}=\dfrac{7.170}{2}}\\\mathsf{S_{7}=7.85}$

$\huge\boxed{\boxed{\boxed{\boxed{\mathsf{S_{7}=595}}}}}$