Question

Ache a soma dos multiplos de 5 compreendidos entre 20 e 258?

Answer 1

PA(25,30,35,...,250,255)
255=25+(n-1).5 => 255:5=25+(n-1) => 51-25=n-1 => 26+1=n => n=27

$S(27)= \frac{27.(25+255)}{2}$
$S(27)= \frac{27.280}{2}$
$S(27)= \frac{7560}{2}$
A soma então é:$S(27)=3780$

Answer 2

1/2.(258-20)
0,5.(258-20)
0.5.238
116